Proxy wars, almost by definition, create risks that extend well beyond the countries on the front line. They’re damaging enough on the ground, but they can also become a soul-sucking quagmire for the big players pulling the strings from a distance. America learned this hard lesson decades ago in Vietnam. So it’s imperative that the Obama administration take decisive action to keep history from repeating itself in Yemen, where a small but destabilizing proxy war seems to be escalating as Houthi rebels with ties to Iran battle a coalition led by Saudi Arabia.

The dangers of a wider conflagration flared recently after Houthi militants fired a missile that came close to a U.S. Navy destroyer cruising the waters between the Red Sea and the Gulf of Aden. The USS Nitze retaliated with what the Pentagon described as “limited self-defense strikes,” by Tomahawk missiles, aimed at Houthi radar installations. Another rebel missile came within 40 miles of the holy city of Mecca, according to Saudi reports.

So far, the Houthi missiles have missed their mark. But that’s merely a lucky break for the U.S., which has been unable to produce a short-term truce, a longer-term strategy in the Arab world’s poorest country, or a path to reducing the regional tensions that seem to be fueling the conflict.

Indeed, there’s growing evidence to support Saudi fears of Iranian involvement. Five weapons shipments, which U.S. officials say were bound for the Houthis, have been seized in the past 18 months. All were traced to Iran, according to U.S. Vice Admiral Kevin Donegan. Iran perceives Saudi Arabia as its main regional rival.

The Saudis, in turn, have launched a relentless air war that has destroyed much of Yemen’s fragile infrastructure. They’ve bombed schools, markets and hospitals. Yemeni officials say that coalition airstrikes on a port city last weekend killed at least 43, many of them inmates in a prison. Normally, the U.S. would do more than just issue a condemnation of such carnage: It would intercept weapons bound for a military with such disregard for civilian life. Instead, the Obama administration has turned on the spigot to the tune of $110 billion in arms sales to Riyadh. Those weapons are being used to cut off supplies of food and medicine to a population that aid groups say is being ravaged by famine and disease. Indeed, Yemen is becoming too deadly to ignore.

There’s a powerful precedent for a political solution, which the U.S. should revisit. In 2013, an initiative in Yemen known as the National Dialogue Conference drew 565 delegates — young people, Houthis, women, and Islamists.

Although that effort stalled, the conference should be resurrected. A political solution could guarantee a secure border for the Saudis, perhaps with a demilitarized zone. The Houthis should be recognized as part of the Yemeni social fabric and should be part of some form of shared governing structure. A settled government would allow the massive humanitarian intervention necessary to rebuild the country. That, finally, is what will keep extremist groups like ISIS and Al-Qaida in the Arabian Peninsula from making further gains. The United States should flex its moral muscle and push for a political solution. To do otherwise will only allow extremist groups to gain the upper hand — with potentially ominous consequences.