In “West Side Story,” the Jets and Sharks both bring weapons to the big rumble — not because either side wants weapons, but just because the other side is going to.

This defense is always used in the case of trade subsidies. It’s how supposed free-traders defend the Export-Import Bank, which subsidizes U.S. exports, mostly Boeing jets — Airbus does it too! they shout.

And it’s how Republican congressman Tom Rooney tried to make a “conservative case” for our federal sugar program, which subsidizes domestic sugar by keeping out foreign sugar — thus forcing consumers and foodmakers to pay higher costs.

Rooney writes:

America’s sugar policy has my support and the support of so many other conservatives because it’s the best line of defense we have against an OPEC-like market that threatens our food security and 142,000 U.S. jobs.

All of the 120 countries that produce sugar have governments that aid their sugar producers and protect their domestic sugar jobs in some way. They have to, because Brazil has used just about every trick in the subsidy handbook to build a market-manipulating empire.

What Rooney doesn’t mention is that the U.S. sugar industry — major Rooney donors, of course — exists only because of government intervention. So, government creates an industry through market distortions, and then the conservative thing to do is distort the market just to protect that industry from subsidized competition?