The Trump administration has been engaged in recent months in an exhaustive review of its Iran policy. Such an assessment is most needed, as the Islamic Republic gained much during the Obama years, projecting its power in all corners of the Middle East. The challenge that confronts the White House is that in the past few years, Iran has crafted an ingenious grand strategy that cheaply promotes its interests.

The Trump administration now confronts not just a truculent theocracy but one that has honed its own strategy for pushing back on the United States. A combination of terrorism and arms control underpin Iran's clever policy of deterring the U.S.

Terrorism works. Since the U.S. invasion of Iraq, Iran has steadily inflamed that nation's sectarian cleavages as a means of enhancing its power. It has trained and armed Shia militias responsive to its Revolutionary Guard commanders.

It was those militias and Iranian munitions that lacerated U.S. troops. In the dark days of Iraqi civil war, Iran was responsible for its share of U.S. casualties and deaths. This has scared the U.S. military, which now has approximately 6,000 troops redeployed back in Iraq. This is just enough to be vulnerable to Iranian terror but not enough to disarm its proxies and pacify Iraq of its nefarious influence.

The Islamic Republic's case is simple: Should U.S. hold Iran responsible for terrorism, it will respond with terrorism. Many influential voices in Washington are concerned that U.S. troops in Iraq are hostage to Iranian retribution. America's appetite for negating Iran's malign strategies may yet be diminished by Tehran's terror apparatus. Terrorism was once thought of as the weapon of the weak, but in the hands of the clerical oligarchs it is rapidly becoming a doctrine of considerable deterrence.

Since the 1979 Iranian revolution, the U.S. has sought to temper the Islamist regime's power by imposing economic sanctions. Successive U.S. administrations labored hard to induce Iran's trading partners to lessen their investments and their purchase of Iranian oil. America sought to segregate Iran from the global financial institutions and thus make its commerce more expensive.

The nuclear agreement with Iran (the Joint Comprehensive Plan of Action) has largely disabled that tactic. Much of the text of the agreement is devoted to economic penalties that are waived, lifted, or altogether disbanded.

Trade delegations and contract signing ceremonies are now the order of the day in Tehran. It is important to stress that Iran agreed to the nuclear accord not just to gain sanctions relief, but to make it impossible for the U.S. to ever again impose a punitive sanctions regime. Too many deals are being signed and too many companies are moving into Iran for America's partner to once more concede to sanctions regime designed to punish Iran for its imperial rampage across the Middle East.

History has ordained that all arms control accords must generate their own constituents. The most important defenders of the JCPOA are not to be found in European corporate boardrooms but in Washington itself.

Many within the Democratic Party wish to avoid a confrontation with Iran lest it jeopardize the nuclear agreement. In the Democratic Party's catechism, the JCPOA stands as a legacy to preserve as opposed to a deficiency to correct. The Democrats can be counted on to avoid sanctions or water-down sanctions bills coming out of the remaining hawkish sectors of Congress. A combination of market forces unleashed by the JCPOA and arms control compulsions of the Democratic Party militate against truly coercive sanctions as a plausible tool of U.S. statecraft.

All this is not to suggest the U.S. is inherently at a disadvantage in confronting Iran. A bold policy of pressuring Iran must puncture these formidable obstacles and accept a measure of risk.

There will be a possibility of a confrontation with Iran in the contested lands of Iraq and Syria should Washington prove serious about limiting Tehran's pernicious influence in the region. This requires enhancement of American capabilities in terms of troops deployed in the region. A policy of imposing economic penalties on Iran for its regional aggression and domestic human rights abuses may in fact cause a degree of consternation among allies which has to be managed with diplomatic care.

The notion that the U.S. should be restrained by the JCPOA ignores the fact that the accord is a deficient agreement whose permissive technical provisions have to be revisited. The notion of rigorously enforcing the agreement only means upholding an accord that puts Iran on a steady and legal path to the bomb.

In the end, Iran today enjoys deterrence on the cheap. Terrorism and the JCPOA have shielded it from real costs. A wise policy should start with the obvious: the confrontation between Iran and the U.S. is a conflict between a superpower with global reach and a local regime detested by its public and distrusted by its neighbors.

The Islamic Republic retreats only when confronted with resolution and strength. For the Trump administration to succeed in the Middle East, it has to not just destroy the Islamic State. but defang the Islamic Republic.

Ray Takeyh is a contributor to the Washington Examiner's Beltway Confidential blog. He is the Hasib J. Sabbagh Senior Fellow for Middle East Studies at the Council on Foreign Relations.

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