Tens of thousands of longshoremen are on strike.BRYAN R. SMITHDockworkers walked off the job at East and Gulf Coast ports from Maine to Texas on Tuesday morning.The strike is set to disrupt major imports one month before the US election.The federal government could step in to mediate, but the upcoming election complicates things.Tens of thousands of dockworkers are on strike after the International Longshoremen's Association and the US Maritime Alliance, which represents dozens of East and Gulf Coast ports, failed to reach consensus on a new labor contract.The walkout is set to shutter 36 ports in the region, according to the Associated Press, which handle about half of all US ocean imports and could cost the economy $540 million per day, according to an analysis from The Conference Board.