The concept of 'just in time' (JIT) shipping of parts, relying on the supply chain's timeliness instead of a massive - and expensive - warehouse of parts, is a fairly recent one, but it has found a home in most major industries thanks to its efficiency. New regulations in the U.S. Customs and Border Protection Bureau (CBP) are threatening the JIT model, however, in the name of national security, and carmakers aren't happy.

The proposal would have the CBP collect detailed information about all imports of items that fall into ten specific categories. Those items would have to be held in port for 24 hours before being loaded onto the source ships headed for the U.S. Then the shipping company would have to declare the cargo's physical location onboard the U.S.-bound ship along with updates if the container is moved, reports The Detroit News. This program would introduce an extra day at least into the JIT model, but would also add the potential for unpredictable delays and backlogs, making the JIT model of distribution unworkable, the industry fears. That would result in significant costs, as would any delays in receiving essential parts or supplies.

According to the government, the new CBP regulations would apply to about 11 million cargo containers carried across the seas to the U.S. in 50,000 trips made by 1,200 ships each year. The industry thinks that magnitude of impact will result in at least $20 billion in costs to their supply networks annually, while the government's estimate is a mere $690 million. Clearly, the two sides are using different models.

The so-called '10+2' rule was proposed at the beginning of this year after about six years of development. Its goal is to decrease the likelihood of a terrorist attack in the U.S. by raising the inspection level on the millions of cargo containers entering the U.S. by its ports each year.

Car industry companies, already pressed with the tough economy and high oil prices, are asking the government for more lenient regulations that would allow them to keep their supply chains as short as possible, thereby keeping costs at a minimum. The CBP wants a ruling on the new regulations by November, though, so the fight could be a short one, however fierce.