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Anyone who has seen “On the Waterfront” knows East Coast longshoremen can be a tough bunch. 
  
 The dockworkers are flexing their muscles again, threatening a strike beginning Sunday that would shut seaports from Massachusetts to Texas. It would be the first such coastwide strike since a two-month walkout in 1977 paralyzed the flow of tens of billions of dollars of imports — and the nation’s retailers and other businesses fear a painful replay if the 14,500 dockworkers make good on their threats. 
  
 “Unless something miraculous happens, I think we’re looking at a strike,” said Kevin M. Burke, president of the American Apparel and Footwear Association, which represents an industry that imports $72 billion in dresses, shoes and other goods each year through the East Coast and Gulf Coast ports facing a possible shutdown. 
  
 “Our companies are preparing for the worst,” Mr. Burke said, “but hoping for the best.” 
  
 The strike threat has so alarmed corporate America that more than 100 business groups wrote to President Obama last week to urge him to intervene to push the two sides to settle — and, if need be, to invoke his emergency powers under the 1947 Taft-Hartley Act to bar a strike. President George W. Bush invoked the act in 2002 to end a lockout at ports on the West Coast, where a different union represents dockworkers. 
  
 Despite their small numbers, the East Coast dockworkers have outsize influence. Many of them, like the crane operators who transfer containers from ships to the docks, are highly skilled and cannot be easily replaced. And because they control the loading and unloading of goods in most of the nation’s ports, a strike could cause extensive economic damage at a time when the economy is already weak. 
  
 “They’re in a crucial place in the flow of goods,” said Richard W. Hurd, an industrial relations professor at Cornell University. 
  
 The Port Authority of New York and New Jersey estimates that a strike would cost the region $136 million a week in personal income and $110 million in economic output. 
  
 The dockworkers union, the International Longshoremen’s Association, opposes presidential intervention, and labor specialists say Mr. Obama, like previous union-friendly Democrats, may be reluctant to enjoin a strike. On the other hand, the economy already faces a potential blow from tax increases and federal budget cuts scheduled to begin on Jan. 1, and a strike would cause further damage. 
  
 “The last thing the nation needs right now is a strike that would shut down the East Coast and Gulf Coast ports,” said Jonathan Gold, the National Retail Federation’s vice president for supply chain policy. “This will have a huge ripple effect throughout the economy.” 
  
 The 14 ports threatened with a strike — including Boston; New York-New Jersey; Baltimore; Charleston, S.C.; Savannah, Ga.; Miami; and Houston — handled 110 million tons of cargo last year. 
  
 The contract negotiations, which have continued fitfully for nine months, broke off on Dec. 18. At the behest of a federal mediator, the two sides are planning to resume talks this week to try to reach a deal before the deadline of 12:01 a.m. Sunday. 
  
 Although several issues need to be resolved, the two sides are deadlocked over one point in particular. The United States Maritime Alliance, an association of shipping companies and terminal owners, is demanding concessions on “container royalty payments,” which the companies share with union members for each ton of cargo handled. The companies want to freeze those payments for current longshoremen and eliminate them for future hires. 
  
 The maritime alliance, known as USMX, says it paid $211 million in container royalties to the longshoremen last year, averaging $15,500 per eligible worker. James A. Capo, the alliance’s chairman, said that came to $10 an hour, on top of what he said were already generous wages. 
  
 “This issue seems to have dwarfed anything else,” Mr. Capo said. “All it does is make the union more uncompetitive than it already is.” 
  
 The alliance says that, including the royalties, the longshoremen earn $124,000 a year on average in wages and benefits. Union officials say those figures are misleading and put average annual wages at $75,000 before benefits — still far more than most union members earn. 
  
 The container payments were created in the 1960s to compensate the longshoremen as ports embraced automation and the use of standardized, 40-foot-long containers to ship goods. That caused a big decrease in jobs and working hours. Employment of longshoremen in the Port of New York and New Jersey has dropped to 3,500 from 35,000 in the 1960s. 
  
 The shipping companies see the royalty payments as a relic of decades past, while the union still sees them as a core part of wages and as an important way to share productivity gains with members. 
  
 The dockworkers union is digging in on the issue. 
  
 “We have repeatedly asked them to leave this item alone,” said Harold J. Daggett, the union’s president. 
  
 Last week, a federal mediator asked the two sides to extend their contract until Feb. 1. But Mr. Daggett ruled out an extension unless USMX dropped its demands on the royalty payments. ||||| Thousands of U.S. dock workers could walk off the job on Sunday, stalling 40 percent of the nation's containerized cargo traffic and potentially hurting retailers and manufacturers still struggling to find their footing in a weak economy. 
  
 FILE - In this Dec. 18, 2012 file photo, a truck driver watches as a freight container, right, is lowered onto a tractor trailer by a container crane at the Port of Boston in Boston. The crane and a reach... (Associated Press) 
  
 The work stoppage by 14,000 longshoremen would immediately close cargo ports on the East Coast and the Gulf of Mexico to container ships and could cause shipments as varied as flat-screen TVs and sneakers to sit idle at sea or get rerouted at great time and expense. 
  
 The White House has weighed in on the issue, urging dockworkers and shipping companies Thursday to reach agreement "as quickly as possible" on a contract extension. 
  
 The 15 ports involved in the labor dispute move more than 100 million tons of goods each year. Losing them to a shutdown, even for a few days, could cost the economy billions of dollars. 
  
 "If the port shuts down, nothing moves in or out," said Jonathan Gold, vice president of supply chain and customs policy at the National Retail Federation. And when the workers do return, "it's going to take time to clear out that backlog, and we don't know how long that it's going to take." 
  
 In addition to transporting goods, U.S. factories also rely on container ships for parts and raw materials, meaning supply lines for all sorts of products could be squeezed. 
  
 "The global economy moves by water, and shutting down container ports along the East and Gulf coasts while the national economy remains fragile benefits no one," Deborah Hadden, acting port director at Massport, the public agency that oversees shipping terminals in Boston. It is not a part of the contract dispute. 
  
 The master contract between the International Longshoremen's Association and the U.S. Maritime Alliance, a group representing shipping lines, terminal operators and port associations, expired in September. The two sides agreed to extend it once already, for 90 days, but they have so far balked at extending it again when it expires at 12:01 a.m. Sunday. 
  
 The union said its members would agree to an extension only if the Maritime Alliance dropped a proposal to freeze the royalties workers get for every container they unload. The Alliance has argued that the longshoremen, who it said earn an average $124,138 per year in wages and benefits, are compensated well enough already. 
  
 Federal mediators have been trying to push negotiations along, but there has been no word from either side on the progress of the talks since Dec. 24. As recently as Dec. 19, the president of the longshoremen, Harold Daggett, said the talks weren't going well and that a strike was expected. 
  
 The work stoppage would not be absolute. Longshoremen would continue to handle military cargo, mail, passenger ships, non-containerized items like automobiles and perishable commodities like fresh food. 
  
 Joseph Ahlstrom, a professor at the State University of New York's Maritime College and a former cargo ship captain, called container ships the "lifeblood of the country." 
  
 "We don't fly in a lot of products. It's just too expensive," Ahlstrom said. "The bulk of the products we import come in inside containers." 
  
 If it happens, the walkout could be the biggest national port disruption since 2002, when unionized dockworkers were locked out of 29 West Coast ports for 10 days because of a contract dispute. 
  
 The ports only reopened after President George W. Bush ordered an 80-day cooling-off period. Some economists estimated that each day of that lockout cost the U.S. economy $1 billion. It took months for the retail supply chain to fully recover. 
  
 An East Coast port freeze would have its biggest impact at the Port Authority of New York and New Jersey, where 3,250 longshoremen handled 32.3 million tons of cargo in 2010. The authority is not a party to the contract dispute. 
  
 Thousands of other jobs would be directly affected by the shutdown. Truck drivers might not have any cargo to transport, tug boat captains no ships to guide and freight train operators nothing to haul. 
  
 ___ 
  
 Associated Press writers Ken Thomas in Washington and Tamara Lush in Tampa, Florida, contributed to this report. |||||


assistant: – Some 14,500 dockworkers are ready to walk out on strike Sunday, and it could shutter ports from Boston to Houston and choke the US economy big-time. The longshoremen are "in a crucial place in the flow of goods," says one professor; New York and New Jersey officials say a strike could drain the region to the tune of $110 million in economic output and $136 million per week in personal income, the New York Times reports. The International Longshoremen's Association is fighting the United States Maritime Alliance, a trade group, over what are known as "container royalty payments." Those payments, in place since the 1960s, amount to about $10 per hour for the workers. The Maritime Alliance holds that the longshoremen make some $124,000 a year, including benefits, while the union says members make more like $75,000, though that doesn't include benefits. "Unless something miraculous happens, I think we’re looking at a strike," says a clothing industry rep. Some 100 industry organizations aren't taking that threat lightly, and have called on President Obama to push for a settlement; the White House weighed in on Thursday.