2091

TWENTY-FIRST AMENDMENT 

REPEAL OF THE EIGHTEENTH AMENDMENT 

CONTENTS

Page

Repeal of Eighteenth Amendment ........................................................................................... 2093 

Effect of Repeal ................................................................................................................... 2093 

Scope of Regulatory Power Conferred upon the States ................................................... 2093 

Discrimination Between Domestic and Imported Products ..................................... 2093 

Regulation of Transportation and ‘‘Through’’ Shipments ........................................ 2095 

Regulation of Imports Destined for a Federal Area ................................................. 2096 

Foreign Imports, Exports; Taxation, Regulation ...................................................... 2097 

Effect of Section 2 upon Other Constitutional Provisions ....................................... 2097 

Effect on Federal Regulation ............................................................................................. 2100 

2093

1 299 U.S. 59 (1936). 

REPEAL OF THE EIGHTEENTH AMENDMENT 

TWENTY-FIRST AMENDMENT 

SECTION 1. The eighteenth article of amendment to the 

Constitution of the United States is hereby repealed. 

SECTION 2. The transportation or importation into any 

State, Territory, or possession of the United States for delivery 

or use therein of intoxicating liquors, in violation of the laws 

thereof, is hereby prohibited. 

SECTION 3. This article shall be inoperative unless it shall 

have been ratified as an amendment to the Constitution by conventions in the several States, as provided in the Constitution, 

within seven years from the date of the submission hereof to 

the States by the Congress. 

REPEAL OF THE EIGHTEENTH AMENDMENT 

Effect of Repeal 

The operative effect of section 1, repealing the Eighteenth 

Amendment, is considered in the commentary dealing with that 

Amendment.

Scope of Regulatory Power Conferred upon the States 

Discrimination Between Domestic and Imported Products.—In a series of interpretive decisions rendered shortly after 

ratification of the Twenty-first Amendment, the Court established 

the proposition that States are competent to adopt legislation discriminating against imported intoxicating liquors in favor of those 

of domestic origin and that such discrimination offends neither the 

commerce clause of Article I nor the equal protection and due process clauses of the Fourteenth Amendment. Thus, in State Board of 

Equalization v. Young’s Market Co., 1 a California statute was 

upheld which exacted a $500 annual license fee for the privilege of 

importing beer from other States and a $750 fee for the privilege 

2094 AMDT. 21—REPEAL OF EIGHTEENTH AMENDMENT 

2 304 U.S. 401 (1938). 

3 305 U.S. 391 (1939). 

4 305 U.S. 395 (1939). 

5 299 U.S. 59, 62 (1936). 

6 299 U.S. at 63-64. In the three decisions rendered subsequently, the Court 

merely restated these conclusions. The contention that discriminatory regulation of 

imported liquors violated the due process clause was summarily rejected in Brewing 

Co. v. Liquor Comm’n, 305 U.S. 391, 394 (1939). 7 384 U.S. 35 (1966). 

8 384 U.S. at 42. See United States v. Frankfort Distilleries, 324 U.S. 293, 299 

(1945) and Nippert v. Richmond, 327 U.S. 416, 425 (1946). 

of manufacturing beer; and in Mahoney v. Triner Corp., 2 a Minnesota statute was sustained which prohibited a licensed manufacturer or wholesaler from importing any brand of intoxicating liquor 

containing more than 25 percent alcohol by volume and ready for 

sale without further processing, unless such brand was registered 

in the United States Patent Office. Also validated in Brewing Co. 

v. Liquor Comm’n 3 and Finch & Co. v. McKittrick 4 were retaliation 

laws enacted by Michigan and Missouri, respectively, by the terms 

of which sales in each of these States of beer manufactured in a 

State already discriminating against beer produced in Michigan or 

Missouri were rendered unlawful. 

Conceding, in State Board of Equalization v. Young’s Market 

Co., 5 that ‘‘prior to the Twenty-first Amendment it would obviously 

have been unconstitutional to have imposed any fee for . . . the 

privilege of importation . . . even if the State had exacted an equal 

fee for the privilege of transporting domestic beer from its place of 

manufacture to the [seller’s] place of business,’’ the Court proclaimed that this Amendment ‘‘abrogated the right to import free, 

so far as concerns intoxicating liquors.’’ Inasmuch as the Amendment was viewed as conferring on states an unconditioned authority to prohibit totally the importation of intoxicating beverages, it 

logically followed that any discriminatory restriction falling short of 

total exclusion was equally valid, notwithstanding the absence of 

any connection between such restriction and public health, safety 

or morals. As to the contention that the unequal treatment of imported beer would contravene the equal protection clause, the 

Court succinctly observed that a ‘‘classification recognized by the 

Twenty-first Amendment cannot be deemed forbidden by the Fourteenth.’’ 6

In Seagram & Sons v. Hostetter 7 the Court upheld a state statute regulating the price of intoxicating liquors, asserting that the 

Twenty-first Amendment bestowed upon the States broad regulatory power over the liquor sales within their territories. 8 It was 

also noted that States are not totally bound by traditional commerce clause limitations when they restrict the importation of toxiVerDate Apr<15>2004 14:36 Jun 28, 2004 Jkt 077500 PO 00000 Frm 00002 Fmt 8222 Sfmt 8222 C:\CONAN\CON056.SGM PRFM99 PsN: CON056
AMDT. 21—REPEAL OF EIGHTEENTH AMENDMENT 2095

9 384 U.S. at 35. See, e.g., Hostetter v. Idlewild Liquor Corp., 377 U.S. 324, 330 

(1964) and State Bd. of Equalization v. Young’s Market Co., 299 U.S. 59 (1936). 10 384 U.S. at 35. The Court went on to assert that it was not deciding then 

whether the mode of liquor regulation chosen by a State in such circumstances could 

ever constitute so grave an interference with a company’s operations elsewhere as 

to make the regulation invalid under the commerce clause. Id. at 42–43. 11 384 U.S. at 47. 12 Capital Cities Cable, Inc. v. Crisp, 467 U.S. 691, 714 (1984). 13 467 U.S. at 715 (quoting California Retail Liquor Dealers Ass’n. v. Midcal 

Aluminum, Inc., 445 U.S. 97, 110 (1980)). 14 Bacchus Imports, Ltd., v. Dias, 468 U.S. 263, 276 (1984). See also BrownForman Distillers Corp. v. New York State Liquor Auth., 476 U.S. 573 (1986) (attempt to regulate prices of out-of-state sales); Capital Cities Cable, Inc. v. Crisp, 467 

U.S. 691 (1984) (state’s limited interest in banning wine commercials carried on 

cable TV while permitting various other forms of liquor advertisement is outweighed 

by federal interest in promoting access to cable TV); and 324 Liquor Corp. v. Duffy, 

479 U.S. 335 (1987) (retail price maintenance in violation of Sherman Act). 

cants destined for use, distribution, or consumption within their 

borders. 9 In such a situation the Twenty-first Amendment demands wide latitude for regulation by the State. 10 The Court added 

that there was nothing in the Twenty-first Amendment or any 

other part of the Constitution that required state laws regulating 

the liquor business to be motivated exclusively by a desire to promote temperance. 11

Recent cases have undercut the expansive interpretation of 

state powers in the Young’s Market and Triner Corp. cases. Twenty-first Amendment and Commerce Clause principles are to be harmonized where possible. The Court now phrases the question in 

terms of ‘‘whether the interests implicated by a state regulation are 

so closely related to the powers reserved by the Twenty-first 

Amendment that the regulation may prevail, notwithstanding that 

its requirements directly conflict with express federal policies.’’ 12

‘‘[T]he central power reserved by § 2 of the Twenty-first Amendment [is] that of exercising ‘control over whether to permit importation or sale of liquor and how to structure the liquor distribution 

system.’’’ 13 Because ‘‘[t]he central purpose of the [Amendment] was 

not to empower States to favor local liquor industries by erecting 

barriers to competition,’’ the ‘‘central tenet’’ of the Commerce 

Clause will control to invalidate ‘‘mere economic protectionism,’’ at 

least where the state cannot justify its tax or regulation as ‘‘designed to promote temperance or to carry out any other purpose of 

the . . . Amendment.’’ 14

Regulation of Transportation and ‘‘Through’’ Shipments.—When passing upon the constitutionality of legislation 

regulating the carriage of liquor interstate, a majority of the Justices seemed disposed to by-pass the Twenty-first Amendment and 

to resolve the issue exclusively in terms of the commerce clause 

2096 AMDT. 21—REPEAL OF EIGHTEENTH AMENDMENT 

15 308 U.S. 132 (1939). 16 308 U.S. at 138. 17 314 U.S. 390 (1941). 18 321 U.S. 131 (1944). See also Cartlidge v. Raincey, 168 F.2d 841 (5th Cir. 

1948), cert. denied, 335 U.S. 885 (1948). 19 Arkansas required a permit for the transportation of liquor across its territory, but granted the same upon application and payment of a nominal fee. Virginia 

required carriers engaged in similar through-shipments to use the most direct route, 

carry a bill of lading describing that route, and post a $1000 bond conditioned on 

lawful transportation; and also stipulated that the true consignee be named in the 

bill of lading and be one having the legal right to receive the shipment at destination.

and state power. This trend toward devaluation of the Twenty-first 

Amendment was set in motion by Ziffrin, Inc. v. Reeves 15 wherein

a Kentucky statute, forbidding the transportation of intoxicating 

liquors by carriers other than licensed common carriers, was enforced as to an Indiana corporation, engaged in delivering liquor 

obtained from Kentucky distillers to consignees in Illinois but licensed only as a contract carrier under the Federal Motor Carriers 

Act. After acknowledging that ‘‘the Twenty-first Amendment sanctions the right of a State to legislate concerning intoxicating liquors 

brought from without, unfettered by the Commerce Clause,’’ 16 the

Court then proceeded to found its ruling largely upon decisions 

antedating the Amendment which sustained similar state regulations as a legitimate exercise of the police power not unduly burdening interstate commerce. In the light of the contemporaneous 

cases enumerated in the preceding topic construing the Twentyfirst Amendment as according a plenary power to the States, such 

extended emphasis on the police power and the commerce clause 

would seem to have been unnecessary. Thereafter, a total eclipse 

of the Twenty-first Amendment was recorded in Duckworth v. Arkansas 17 and Carter v. Virginia, 18 wherein, without even considering that Amendment, a majority of the Court upheld, as not contravening the commerce clause, statutes regulating the transport 

through the State of liquor cargoes originating and ending outside 

the regulating State’s boundaries. 19

Regulation of Imports Destined for a Federal Area.—Importation of alcoholic beverages into a State for ultimate delivery 

at a National Park located therein but over which the United 

States retained exclusive jurisdiction has been construed as not 

constituting ‘‘transportation . . . into [a] State for delivery and use 

therein’’ within the meaning of § 2 of the Amendment. The importation having had as its objective delivery and use in a federal area 

over which the State retained no jurisdiction, the increased powers 

which the State acquired from the Twenty-first Amendment were 

declared to be inapplicable. California therefore could not extend 

AMDT. 21—REPEAL OF EIGHTEENTH AMENDMENT 2097

20 Collins v. Yosemite Park Co., 304 U.S. 518, 537–38 (1938). The principle was 

reaffirmed in United States v. Mississippi Tax Comm’n, 412 U.S. 363 (1973), holding 

that Mississippi could not apply its tax regulations to liquor sold to military officers’ 

clubs and other nonappropriated fund activities located on bases within the State 

and over which the United States had obtained exclusive jurisdiction. ‘‘Absent an 

appropriate express reservation . . . the Twenty-first Amendment confers no power 

on a State to regulate—whether by licensing, taxation, or otherwise—the importation of distilled spirits into territory over which the United States exercises exclusive jurisdiction.’’ Id. at 375. Nor may states tax importation of liquor for sale at 

bases over which the United States exercises concurrent jurisdiction only. United 

States v. Mississippi Tax Comm’n, 421 U.S. 599 (1975). 21 North Dakota v. United States, 495 U.S. 423 (1990) (also upholding application to federal enclaves of a uniform requirement that shipments into the state be 

reported to state officials). 22Department of Revenue v. Beam Distillers, 377 U.S. 341 (1964). The Court 

distinguished Gordon v. Texas, 355 U.S. 369 (1958) and De Bary v. Louisiana, 227 

U.S. 108 (1913). 23 Hostetter v. Idlewild Liquor Corp., 377 U.S. 324 (1964). 24 Brown-Forman Distillers Corp. v. New York State Liquor Auth., 476 U.S. 573, 

585 (1986) (citation omitted). Accord, Healy v. Beer Institute, 491 U.S. 324 (1989). 

the importation license and other regulatory requirements of its Alcoholic Beverage Control Act to a retail liquor dealer doing business in the Park. 20 On the other hand, a state may apply nondiscriminatory liquor regulations to sales at federal enclaves under 

concurrent federal and state jurisdiction, and may require that liquor sold at such federal enclaves be labelled as being restricted for 

use only within the enclave. 21

Foreign Imports, Exports; Taxation, Regulation.—The

Twenty-first Amendment did not repeal the export-import clause, 

Art. I, § 10, cl. 2, nor obliterate the commerce clause, Art. I, § 8, 

cl. 3. Accordingly, a State cannot tax imported Scotch whiskey 

while it remains ‘‘in unbroken packages in the hands of the original 

importer and prior to [his] resale or use’’ thereof. 22 Likewise, New 

York is precluded from terminating the business of an airport dealer who, under sanction of federal customs laws, acquired ‘‘tax-free 

liquors for export’’ from out-of-state sources for resale exclusively to 

airline passengers, with delivery deferred until the latter arrive at 

foreign destinations. 23 Similarly, a state ‘‘affirmation law’’ prohibiting wholesalers from charging lower prices on out-of-state sales 

than those already approved for in-state sales is invalid as a direct 

regulation of interstate commerce. ‘‘The Commerce Clause operates 

with full force whenever one State attempts to regulate the transportation and sale of alcoholic beverages destined for distribution 

and consumption in a foreign country . . . or another State.’’ 24

Effect of Section 2 upon Other Constitutional Provisions.—Nothwithstanding the 1936 assertion that ‘‘[a] classification recognized by the Twenty-first Amendment cannot be deemed 

2098 AMDT. 21—REPEAL OF EIGHTEENTH AMENDMENT 

25State Bd. of Equalization v. Young’s Market Co., 299 U.S. 59, 64 (1936). In 

Craig v. Boren, 429 U.S. 190, 206–07 (1976), this case and others like it are distinguished as involving the importation of intoxicants into a State, an area of increased 

state regulatory power, and as involving purely economic regulation traditionally 

meriting only restrained review. Neither distinguishing element, of course, addresses the precise language quoted. For consideration of equal protection analysis in an 

analogous situation, the statutory exemption of state insurance regulations from 

commerce clause purview, see Western & Southern Life Ins. Co. v. State Bd. of 

Equalization, 451 U.S. 648, 655–74 (1981). 26 429 U.S. 190 (1976). 27 429 U.S. at 206 (quoting P. BREST, PROCESSES OF CONSTITUTIONAL DECISIONMAKING—CASES AND MATERIALS 258 (1975). 28 429 U.S. at 209-210. 29 E.g., Moose Lodge No. 107 v. Irvis, 407 U.S. 163, 178–97 (1972) (invalidating 

a state liquor regulation as an equal protection denial in a racial context); Wisconsin 

v. Constantineau, 400 U.S. 433 (1971) (invalidating a state law authorizing the posting of someone as an ‘‘excessive drinker’’ and thus barring him from buying liquor, 

as reconstrued in Paul v. Davis, 424 U.S. 693, 707–09 (1976)). 30Larkin v. Grendel’s Den, Inc., 459 U.S. 116, 122 n.5 (1982). 31 409 U.S. 109 (1972). 

forbidden by the Fourteenth,’’ 25 the Court has now in a series of 

cases acknowledged that § 2 of the Twenty-first Amendment did 

not repeal provisions of the Constitution adopted before ratification 

of the Twenty-first, save for the severe cabining of commerce clause 

application to the liquor traffic, but it has formulated no consistent 

rationale for a determination of the effect of the later provision 

upon earlier ones. In Craig v. Boren, 26 the Court invalidated a 

state law that prescribed different minimum drinking ages for men 

and women as violating the equal protection clause. To the State’s 

Twenty-first Amendment argument, the Court replied that the 

Amendment ‘‘primarily created an exception to the normal operation of the Commerce Clause’’ and that its ‘‘relevance . . . to other 

constitutional provisions’’ is doubtful. ‘‘‘Neither the text nor the history of the Twenty-first Amendment suggests that it qualifies individual rights protected by the Bill of Rights and the Fourteenth 

Amendment where the sale or use of liquor is concerned.’’’ 27 The

square holding on this point is ‘‘that the operation of the Twentyfirst Amendment does not alter the application of the equal protection standards that would otherwise govern this case.’’ 28 Other decisions reach the same result but without discussing the application of the Amendment. 29 Similarly, a state ‘‘may not exercise its 

power under the Twenty-first Amendment in a way which impinges 

upon the Establishment Clause of the First Amendment.’’ 30

The Court departed from this line of reasoning in California v. 

LaRue. 31 There, the Court sustained the facial constitutionality of 

regulations barring a lengthy list of actual or simulated sexual activities and motion picture portrayals of these activities in establishments licensed to sell liquor by the drink. In an action attackVerDate Apr<15>2004 14:36 Jun 28, 2004 Jkt 077500 PO 00000 Frm 00006 Fmt 8222 Sfmt 8222 C:\CONAN\CON056.SGM PRFM99 PsN: CON056
AMDT. 21—REPEAL OF EIGHTEENTH AMENDMENT 2099

32 Cf. Schad v. Borough of Mount Ephraim, 452 U.S. 61 (1981) (ban on live nude 

dancing in Borough); Doran v. Salem Inn, 422 U.S. 922 (1975) (ban on nude dancing 

in ‘‘any public place’’ applied to topless dancing in bars). 33 409 U.S. at 114-19. In Doran v. Salem Inn, 422 U.S. 922, 932–33 (1975), the 

Court described its holding in LaRue more broadly, saying that ‘‘we concluded that 

the broad powers of the States to regulate the sale of liquor, conferred by the Twenty-first Amendment, outweighed any First Amendment interest in nude dancing and 

that a State could therefore ban such dancing as part of its liquor license control 

program.’’ 34 New York State Liquor Auth. v. Bellanca, 452 U.S. 714, 717 (1981). 35For a rejection of the argument in another context, contemporaneously with 

Bellanca, see Western & Southern Life Ins. Co. v. State Bd. of Equalization, 451 

U.S. 648, 657–68 (1981). And for utilization of the argument in the commercial 

speech context, see Posadas de Puerto Rico Associates v. Tourism Co. of Puerto Rico, 

478 U.S. 328, 345–46 (1986). But see Capital Cities Cable, Inc. v. Crisp, 467 U.S. 

691 (1984), not addressing the commercial speech issue but holding state regulation 

of liquor advertisements on cable TV to be preempted, in spite of the Twenty-first 

Amendment, by federal policies promoting access to cable TV). 36 517 U.S. 484 (1996) (statutory prohibition against advertisements that provide the public with accurate information about retail prices of alcoholic beverages 

is not shielded from constitutional scrutiny by the Twenty-first Amendment). 

ing the validity of the regulations as applied to ban nude dancing 

in bars, the Court considered at some length the material adduced 

at the public hearings which resulted in the rules demonstrating 

the anti-social consequences of the activities in the bars. It conceded that the regulations reached expression that would not be 

deemed legally obscene under prevailing standards and reached expressive conduct that would not be prohibitable under prevailing 

standards, 32 but the Court thought that the constitutional protection of conduct that partakes ‘‘more of gross sexuality than of communication’’ was outweighed by the State’s interest in maintaining 

order and decency. Moreover, the Court continued, the second section of the Twenty-first Amendment gave an ‘‘added presumption 

in favor of the validity’’ of the regulations as applied to prohibit 

questioned activities in places serving liquor by the drink. 33

A much broader ruling was forthcoming when the Court considered the constitutionality of a state regulation banning topless 

dancing in bars. ‘‘Pursuant to its power to regulate the sale of liquor within its boundaries, it has banned topless dancing in establishments granted a license to serve liquor. The State’s power to 

ban the sale of alcoholic beverages entirely includes the lesser 

power to ban the sale of liquor on premises where topless dancing 

occurs.’’ 34 This recurrence to the greater-includes-the-lesser-power 

argument, relatively rare in recent years, 35 would if it were broadly applied give the States in the area of regulation of alcoholic beverages a review-free discretion of unknown scope. 

In 44 Liquormart, Inc. v. Rhode Island, 36 the Court disavowed 

LaRue and Bellanca, and reaffirmed that, ‘‘although the TwentyVerDate Apr<15>2004 14:36 Jun 28, 2004 Jkt 077500 PO 00000 Frm 00007 Fmt 8222 Sfmt 8222 C:\CONAN\CON056.SGM PRFM99 PsN: CON056
2100 AMDT. 21—REPEAL OF EIGHTEENTH AMENDMENT 

37 517 U.S. at 516 (quoting Capital Cities Cable, Inc., v. Crisp, 467 U.S. 691, 

712 (1984)). 38 517 U.S. at 515. 39 United States v. Frankfort Distilleries, 324 U.S. 293, 297–99 (1945). 40 324 U.S. at 301-02. For application of federal laws, see William Jameson & 

Co. v. Morgenthau, 307 U.S. 171 (1939); Kiefer-Stewart Co. v. Joseph E. Seagram 

& Sons, 340 U.S. 211 (1951); Schwegmann Bros. v. Calvert Corp., 341 U.S. 384 

(1951); Joseph E. Seagram & Sons v. Hostetter, 384 U.S. 35 (1966); Burke v. Ford, 

389 U.S. 320 (1967). 

first Amendment limits the effect of the dormant Commerce Clause 

on a state’s regulatory power over the delivery or use of intoxicating beverages within its borders, ‘the Amendment does not license the States to ignore their obligations under other provisions 

of the Constitution,’’’ 37 and therefore does not afford a basis for 

state legislation infringing freedom of expression protected by the 

First Amendment. There is no reason, the Court asserted, for distinguishing between freedom of expression and the other constitutional guarantees (e.g., those protected by the Establishment and 

Equal Protection Clauses) held to be insulated from state impairment pursuant to powers conferred by the Twenty-first Amendment. The Court hastened to add by way of dictum that states retain adequate police powers to regulate ‘‘grossly sexual exhibitions 

in premises licensed to serve alcoholic beverages.’’ ‘‘Entirely apart 

from the Twenty-first Amendment, the State has ample power to 

prohibit the sale of alcoholic beverages in inappropriate locations.’’ 38

Effect on Federal Regulation 

The Twenty-first Amendment does not oust all federal regulatory power affecting transportation or sale of alcoholic beverages. 

Thus, the Court held, the Amendment does not bar a prosecution 

under the Sherman Antitrust Act of producers, wholesalers, and retailers charged with conspiring to fix and maintain retail prices of 

alcoholic beverages in Colorado. 39 In a concurring opinion, supported by Justice Roberts, Justice Frankfurter took the position 

that if the State of Colorado had in fact ‘‘authorized the transactions here complained of, the Sherman Law could not override 

such exercise of state power. . . . [Since] the Sherman Law . . . can 

have no greater potency than the Commerce Clause itself, it must 

equally yield to state power drawn from the Twenty-first Amendment.’’ 40

Following a review of the cases in this area, the Court has observed ‘‘that there is no bright line between federal and state powers over liquor. The Twenty-first Amendment grants the States virtually complete control over whether to permit importation or sale 

of liquor and how to structure the liquor distribution system. AlVerDate Apr<15>2004 14:36 Jun 28, 2004 Jkt 077500 PO 00000 Frm 00008 Fmt 8222 Sfmt 8222 C:\CONAN\CON056.SGM PRFM99 PsN: CON056
AMDT. 21—REPEAL OF EIGHTEENTH AMENDMENT 2101

41 California Retail Liquor Dealers Ass’n v. Midcal Aluminum, 445 U.S. 97, 110 

(1980). 42South Dakota v. Dole, 483 U.S. 203, 210 (1987). 

though States retain substantial discretion to establish other liquor 

regulations, those controls may be subject to the federal commerce 

power in appropriate situations. The competing state and federal 

interests can be reconciled only after careful scrutiny of those concerns in a ‘concrete case.’’’ 41 Invalidating under the Sherman Act 

a state fair trade scheme imposing a resale price maintenance policy for wine, the Court balanced the federal interest in free enterprise expressed through the antitrust laws against the asserted 

state interests in promoting temperance and orderly marketing 

conditions. Since the state courts had found the policy under attack 

promoted neither interest signficantly, the Supreme Court experienced no difficulty in concluding that the federal interest prevailed. 

Whether more substantial state interests or means more suited to 

promoting the state interests would survive attack under federal 

legislation must await further litigation. 

Congress may condition receipt of federal highway funds on a 

state’s agreeing to raise the minimum drinking age to 21, the 

Twenty-first Amendment not constituting an ‘‘independent constitutional bar’’ to this sort of spending power exercise even though 

Congress may lack the power to achieve its purpose directly. 42