The New York Times has a pretty good account of how the Jones Act is delaying the arrival of road salt to New Jersey for use on the state's icy roads:
State officials said they arranged on Feb. 7 to buy the salt and ship it immediately to Port Newark on a vessel that had just unloaded its cargo in Maine and would have delivered the entire load to New Jersey by last weekend.
But then officials learned that the maritime law, which was passed in 1920 and is known as the Jones Act, stipulates that only ships with United States flags and crews can transport goods between American ports. They applied for the waiver on Thursday, but the Department of Homeland Security has not yet ruled on it.
Such waivers are issued infrequently — limited ones were granted after Hurricane Katrina and Hurricane Sandy to expedite fuel shipments — but New Jersey officials argued that the state was facing a dire situation. Some municipalities, officials said, were being forced to seek alternatives, including mixing sand into rock salt and using a briny mixture similar to pickle juice as supplements.
The Jones Act was pushed through Congress after World War I by Senator Wesley Jones of Washington, who warned that foreign nations would use "fair means and foul" to keep America from taking a leading role in the global shipping trade.
The law has prompted fierce debate over the years, with opponents painting it as anti-competitive and a boon for unions while supporters still see it as vital to national security.
As we wrote back in November of 2012, "Instead of just waiving the Jones Act to get gas into NYC, as Obama admin just did, why not go all the way and repeal it?"