NEW YORK (Michigan News Source) – Tens of thousands of longshoremen at ports along the East Coast and the Gulf of Mexico are on strike as of Tuesday morning. It marks the first strike by the port workers’ union in 47 years.

Workers from Maine to Texas walked off the job at 12:01 a.m. on Tuesday after the United States Maritime Alliance (USMX) and the International Longshoremen’s Association (ILA) failed to reach an agreement by the deadline.

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The union sought wage increases and a ban on the automation of cranes, gates, and container-moving trucks.

Many retailers frontloaded shipments or diverted shipping through the West Coast in anticipation of the walkout, and businesses are bracing for a long strike.

The economic impact is predicted to be substantial. Business research nonprofit The Conference Board puts the cost at around $540 million per day, while JP Morgan analysts estimate a $5 billion daily cost.