CP Industries just got an expensive lesson in the unintended consequences of protectionism.

Based in McKeesport, Pa., the company makes seamless vessels to store gases at high pressure — steel cylinders of up to six tons that it sells to the likes of the Navy, NASA and T. Boone Pickens’s Clean Energy. It has received the first bill from the 25 percent tariff that President Trump placed on steel from China and a few other countries: $178,703.09 assessed on a steel-pipe shipment scheduled to arrive at the Port of Philadelphia on Thursday.

That’s equivalent to about two weeks’ payroll. Over all, tariffs on steel pipe that the company has ordered from China — some already on its way across the Pacific — will add more than half a million dollars to raw-material costs over six months alone.

“How long can we last?” mused Michael Larsen, the company’s chief executive. “I don’t know. We could go down relatively fast.”