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 —

The stoppage is the first coast-wide ILA strike since 1977 and halts the flow of about half the nation's ocean shipping. A two-week strike could mean that ports would not return t