Iran sanctions by U.S. will have limited effect

There is a case to be made for tougher sanctions on Iran, such as those imposed Monday by the Trump administration.

Since signing the 2015 accord limiting its nuclear program, Tehran has only stepped up its aggressions.

It has supplied missiles to Houthi rebels in Yemen for use against Saudi Arabia, and it has smuggled them into Lebanon and Syria for potential use against Israel.

It has been caught twice in four months trying to murder opponents in European countries.

President Barack Obama’s hopes that the nuclear deal would lead to a moderation of Iran’s malign activity were illusory.

Now, having withdrawn from that pact — unwisely, in our view — President Donald Trump is betting that the resumption of harsh sanctions will bring the regime of Ayatollah Ali Khamenei to heel.

While the punishment may be justified, the chance of a sea change in Tehran remains small.

The new measures targeting Iranian oil exports, shipping and banks may reduce Tehran’s oil exports to about a third of their recent peak of 2.8 million barrels a day, according to analysts.

That will considerably dent the government’s budget and perhaps tip Iran back into recession.

But the embargo is unlikely to be as effective as that which brought Iran to the table for nuclear talks.

China, India, Russia and Turkey are among the nations that will continue to buy Iranian oil.

Iran may find it harder to find the billions it is spending on supporting Shiite militias across the Middle East.

But the Revolutionary Guard Corps is unlikely to retreat from Iraq or the Levant, even if the price is more hardship for an already restless population back home.

Senior Trump administration officials clearly hope the renewed economic pressure will trigger a change of regime. But Washington has been waiting in vain for such a counterrevolution since 1979.

Whatever rewards come from squeezing the Islamic republic will probably be accompanied by new costs.

Iran could resume attacks on U.S. targets in Iraq or in Syria, or challenge the diminished U.S. fleet in the Persian Gulf. It could take steps toward resuming its nuclear program — something that would leave the Trump administration with few options short of military action.

If that’s the outcome, Trump’s decision to pull out of the nuclear deal — which international inspectors say Iran has observed — will have spectacularly backfired.

He could have stepped up pressure on Tehran without taking that risk.

Trump says he wants to negotiate a new deal with the mullahs covering more than the nuclear program.

If he is serious about that, he will have to alter his approach. Tehran will never agree to unilaterally abandon its equities in Iraq or elsewhere in the Middle East.

The key to any grand bargain would be finding a peaceful balance of its interests with those of Saudi Arabia and its Sunni allies.

That, in return, would require the Trump administration to retreat from its exaggerated embrace of the regime in Riyadh — which, just like that of Iran, needs to have its aggressions placed in check. Members of The Denver Post’s editorial board are Megan Schrader, editor of the editorial pages; Lee Ann Colacioppo, editor; Justin Mock, CFO; Bill Reynolds, vice president of circulation and production; Bob Kinney, vice president of information technology; and TJ Hutchinson, systems editor.