U.S. ports from Maine to Texas could shut down Tuesday if a union representing about 45,000 dockworkers carries through with a threatened strike. A lengthy shutdown could raise prices on goods around the country and potentially cause shortages and price increases at big and small retailers alike as the holiday shopping season — along with a tight presidential election —

Longshoremen are on strike, shutting down East, Gulf ports. Economic losses of $5 billion per day can mean shortages, inflation and layoffs.