A vicious feud between Iran and Saudi Arabia has been raging for years. The two governments support opposite sides of several civil wars, in what amounts to a regional power struggle between the Sunni and Shia branches of Islam. One might think that the United States would adopt a “plague on both their houses” attitude toward a quarrel between two repulsive, authoritarian regimes. Indeed, that policy would best serve genuine American interests.

But such discreet neutrality does not describe Washington’s stance at any point since Iran’s Islamic Revolution in 1979. Instead, U.S. administrations have tilted decisively in favor of the Saudis. That point was exemplified most recently with President Trump’s fawning visit to Riyadh. Both the president and Secretary of State Rex Tillerson went out of their way to denounce Iran and to reiterate the need for strategic cooperation between the United States and the Kingdom. Trump underscored Washington’s commitment by signing a new $110 billion arms-sale agreement.

Although neutrality would be the best option for America, if U.S. leaders feel that they must meddle in a Middle East power struggle, then they should at least pick the less objectionable side. Instead, they have consistently backed the more dangerous, corrupt, vicious and duplicitous regime. Such an approach deserves an award for myopia.

There are numerous reasons why both Washington and the American people have no love for Tehran. Americans recall the searing images of the U.S. American diplomats who were held hostage at the end of Jimmy Carter’s administration. And Iran was implicated in attacks on U.S. forces in the Middle East, including the bombing of the Marine barracks in Lebanon in 1983 and the 1996 bombing of the Air Force quarters in the Khobar Towers in Saudi Arabia. The American people have developed a visceral hatred of Iran, and political leaders have fanned that hatred by insisting that Iran was (and remains) the chief state sponsor of terrorism. The reality is that the Iranian government backs assorted factions that have attacked either Israeli or Saudi interests. U.S. officials automatically equate such insurgencies with terrorism, which is, at best, an excessively simplistic view.

Washington’s hostility has ebbed just slightly following the agreement between the P5+1 powers and Iran concerning Tehran’s nuclear program. Even that modest rapprochement is now in danger given the Trump administration’s open skepticism about the accord and the increasingly anti-Iranian rhetoric coming from U.S. officials. There is also a concerted lobbying effort by pro-Israeli and pro-Saudi forces in the United States to rescind Washington’s adherence to the agreement and to maintain a hostile stance toward Tehran generally.

The anti-Iranian, pro-Saudi bias has helped entangle America in the complex, bloody conflicts of the Middle East. The bitter rivalry between Tehran and Riyadh is apparent on multiple fronts. A few years ago, Saudi Arabia intervened militarily to prop-up the Sunni ruling family in Bahrain against an increasingly angry majority-Shia population supported by Iran. Riyadh continues to back that corrupt, minority regime.

More recently, the Saudis have led a coalition of Sunni states in the Gulf to intervene in Yemen’s civil war. Riyadh has launched air strikes against Yemen’s Shia Houthis to prevent a victory by that faction, which has received backing from Iran. Saudi Arabia’s military campaign has been marked by a massive human-rights violation and has triggered such chaos in the country that a major famine appears imminent. Yet Washington has backed that war of aggression by providing Saudi forces with intelligence information and logistical support.

The civil wars in Iraq and Syria also constitute theaters in the Sunni-Shia campaign for regional dominance. Iran has supported Iraq’s post-Saddam, Shia-dominated government both financially and militarily. Tehran has provided even greater support to extremist Shia militias in that country. Conversely, Saudi Arabia early on aided the Sunni tribes in Anbar Province and elsewhere in western and northern Iraq that resisted the authority of the new government. Some of those groups eventually coalesced to form ISIS.

The Saudi-Iranian proxy war is even more evident in neighboring Syria. Assad heads what amounts to a “coalition of religious minorities” regime. The main components of that coalition are Christians, Druze and Assad’s own political base, the Alawites, a Shia offshoot. That faction receives strong support from Iran, as well as Tehran’s ally in neighboring Lebanon, Hezbollah. Arrayed against that coalition is an overwhelmingly Sunni insurgency. The rebels have received extensive financial and logistical support from Saudi Arabia and another leading Sunni power, Turkey. Much of that aid has flowed to extremely radical factions. Some of the recruits filled the ranks of ISIS. Others formed the basis of the Jabhat al-Nusra, Al Qaeda’s affiliate in Syria and other, smaller Sunni Islamist groups.

Washington has waffled in its position regarding the Iraqi government. U.S. official support for the Shia-led government remains intact, but the United States has also increased its military backing for Iraqi Kurds, whose secessionist agenda could badly undermine Baghdad’s authority. Washington’s policy in Syria aligns more closely with Riyadh’s objectives, with both the Obama and Trump administration’s openly favoring the insurgency against Assad’s government.

It is difficult to justify the tilt toward Saudi Arabia on either strategic or moral grounds. Strategically, Riyadh may warrant an award for being Washington’s most duplicitous ally. Saudi leaders have undermined America’s security interests for decades. As early as the 1980s, Riyadh made a concerted effort, in collusion with Pakistan, to make sure that the bulk of the financial and military assistance that Washington was providing Afghan insurgents resisting the Soviet occupation went to the most extreme Islamist factions. Alumni of that conflict later became cadres in various terrorist movements.

Numerous analysts have noted that fifteen of the nineteen hijackers on 9/11 were Saudi nationals, but that was hardly the extent of Riyadh’s culpability. Some Saudi officials had at least a disturbingly tolerant relationship with Al Qaeda for years before those attacks. To the everlasting shame of the Bush and Obama administrations, much of the information concerning that association remained concealed from the American people in the infamous, classified twenty-eight pages of the 9/11 Commission Report. Even when those pages were finally released in July 2016, portions were heavily redacted.

Riyadh also has continued to back extremist factions in both Iraq and Syria. The former runs counter to U.S. policy, and the latter differs significantly from Washington’s official (albeit quixotic) search for “moderate” Syrian rebels.

Justifying the fondness for Saudi Arabia on moral grounds is even harder to justify. Aside from Saudi war crimes in Yemen, including the use of banned cluster bombs, Riyadh has a dreadful domestic human-rights record. The regime treats women and religious minorities as third-class citizens, conducts barbaric beheadings and imprisons or executes even peaceful political critics. Saudi Arabia is easily one of the four or five most repressive political and social systems in the world. It is essentially a totalitarian theocracy.

Iran is hardly a model of political tolerance and respect for human rights either, but it compares favorably to Saudi Arabia on both counts. Women have a markedly better status there than in the Saudi kingdom, where they are not even allowed to drive or to go out in public without being accompanied by a male relative. There are competitive (if constrained) elections in Iran featuring candidates with different views. The recent re-election of reformist president Hassan Rouhani over a hardline challenger is the latest example of such democratic features. None of that occurs in Saudi Arabia.

From both a strategic and moral standpoint, Washington should not be backing Saudi Arabia against Iran. Aside from Riyadh’s odious behavior on both fronts, U.S. leaders should be wary of supporting the stronger faction in the Middle East power struggle. There are far more Sunnis than Shia in that region, and Saudi Arabia is—thanks largely to U.S. aid—already the more potent military power. Backing that actor is as myopic as if the Nixon administration had tilted toward Moscow instead of Beijing during the Cold War. In his memoirs, Henry Kissinger notes that elements within the U.S. State Department pushed exactly that policy—which he justifiably viewed with dismay and contempt.

The Trump administration faces a similar, crucial decision. If Washington cannot embrace the wisdom of adopting a neutral stance regarding the Iranian-Saudi feud, administration officials should at least not compound their error by backing the wrong side.

Ted Galen Carpenter, a senior fellow for defense and foreign-policy studies at the Cato Institute and a contributing editor at the National Interest, is the author of ten books, the contributing editor of ten books, and the author of more than 650 articles on international affairs.

Image: A Royal Saudi air force pilot taxis his F-15S. U.S. Air Force photo/Chief Master Sgt. Gary Emery