Nearly 50,000 members of the International Longshoremen’s Association (ILA) are on strike Tuesday against the nation’s East and Gulf Coast ports, choking off the flow of many of the nation’s imports and exports in what could become America’s most disruptive work stoppage in decades.

Tens of thousands of longshoremen at ports along the East Coast and Gulf of Mexico went on strike shortly after midnight, the first strike by the port workers’ union in nearly 50 years. Workers walked off the job from Maine to Texas,