Bear in mind this was written in 1928 in a very different legal context. In particular it was written before the Erie double-reversal [0].

Personally, I think it was poorly drafted by modern standards. Today, this particular exclusion would be something like adding an additional paragraph with text that says "nothing herein shall affect any provision of any other statue" (please excuse my imprecision)

Julius Henry Cohen, one of the key authors of the law, wrote the following (ellipse and elision for emphasis. Please see the full source for full text):

> ... which commands an unusually widespread support in the business world because the reform is directed primarily toward settlement of commercial disputes...

> A written provision for arbitration contained in any contract which involves maritime transactions ... or interstate commerce as generally defined, is made "valid, enforceable and irrevocable,"

> It must be read in the light of the situation which it was devised to correct and of the history of arbitration anid of similar statutes in the recent past.

> The evils which arbitration is intended to correct are three in number: (1) The long delay usuallv incident to a proceeding at law, in equity or in admiralty, especially in recent years in centers of commercial activity, where there has arisen great congestion of the court calendars. nce. (2) The expense of litigation. (3) The failure, through litigation, to reach a decision regarded as just when measured by the standards of the business world.

> Arbitration under the Federal and similar statutes is simply a new procedural remedy, particularly adapted to the settlement of commercial dispute

> 'Information collected by the Department of Commerce over the past several years' hie said, 'clearly showed that the substantial element of the American business public is overwhelmingly in favor of arbitration in the settlement of *commercial disputes* in both domestic and foreign trade

While I don't quote it here, there is also interesting rules around jurisdictions which the law was trying to dance around.

Please also see [2]

58 See Leslie, supranote 57, at 309 ("Congress did not intend the FAA to facilitate firms imposing arbitration clauses on consumers through contracts of adhesion.... For example, in colloquy, when senators raised the issue of contracts of adhesion, the bill's supporters testified that the FAA would not apply to such situations."); id. at 310-11 ("During the earliest hearings for the FAA, concerns were expressed that the Act could cover employment . .. . The Act's text was amended [to exclude] 'contracts of employment of ... any ... class of workers engaged in foreign or interstate commerce.' . . . [T]he amendment appeased labor interests, who removed their opposition to the bill." (footnote omitted) (quoting 9 U.S.C. § 1 (2012))); Margaret L. Moses, Statutory Misconstruction: How the Supreme Court Created a FederalArbitrationLaw Never Enacted by Congress, 34 FLA. ST. U. L. REv. 99, 147 (2006) ("[N]o one in 1925-not the drafters, the Secretary of Commerce, organ ized labor, nor members of Congress-believed that the FAA applied to employment contracts.").

[0] https://www.law.cornell.edu/wex/erie_doctrine

[1] Cohen, J. H., & Dayton, K. (1926). The New Federal Arbitration Law. Virginia Law Review, 12(4), 265–286. https://doi.org/10.2307/1065471 pp 265

[2] Fitzpatrick, B. T. (2017). Justice Scalia and Class Actions. Notre Dame Law Review, 92, 1977. https://scholarship.law.vanderbilt.edu/faculty-publications/... pp 1986 note 58 (via citation)