ABDULJABBAR ZEYAD / Reuters Salem Abduallah Musabih, 6, lies on a bed at a malnutrition intensive care unit at a hospital in the Red Sea port city of Hodaida, Yemen, on Sept. 11. A Saudi-led coalition fighting rebels in Yemen has killed 10,000 people in the last 18 months.

WASHINGTON ― If he wanted to, President Barack Obama could end ― or at least dramatically reduce ― the ongoing slaughter of civilians in Yemen.

Right now, the Saudi-led coalition at war there can direct its jets to spend up to three hours pummeling the starving nation below. If Obama wanted, they might have just minutes instead.

Today, the coalition officials deciding where to drop the bombs can rely on intelligence from U.S. surveillance systems, the most powerful in the world. If Obama wanted, they might run fewer bombing missions because they would have to rely on their own limited targeting data.

At present, the bombs the Saudis and their allies are dropping on hospitals, schools, crowded markets and vital factories are in plentiful supply, and the jets that deliver them are perfectly serviced. But if Obama wanted, those bombers’ capacities could suddenly be severely limited.

Using U.S. support, the Saudi-led coalition fighting Iran-backed rebels in Yemen has been responsible for the majority of the 10,000 deaths there since the conflict began 18 months ago ― and a brutal attack on Saturday that has reportedly killed hundreds. It has left more than 28 million people on the brink of famine. And it has allowed militant Islamists ― notably Al Qaeda in the Arabian Peninsula, which is focused on targeting the U.S. ― to seize more influence and room to operate than they have had in years.

In the public consciousness, this brutal conflict blurs into the other bloody wars across the Middle East, each of them marked by its own complicated mix of players, incentives and grievances that make peace unlikely.

But Yemen is different. Here, Obama could single-handedly cause a major drop in the bloodshed, experts say. He simply doesn’t seem to want to do it.

The Huffington Post

Per Obama’s orders, planes belonging to the Saudis and others involved in their coalition currently receive aerial refueling from American planes, a defense official confirmed to The Huffington Post this week. U.S. military personnel stationed in Saudi Arabia offer intelligence and logistical support to the coalition, but don’t decide where it bombs, the official said. And the Obama administration has greenlit three new transfers of weapons ― ammunition, bombs, air-to-ground missiles and tanks ― to the kingdom to replenish stocks used in Yemen, according to arms trade expert William Hartung.

Obama could stop all of that at any time.

(The White House did not respond to HuffPost’s requests for comment on this proposition.)

“There’s no question that American refueling, providing tankers, greatly enables the bombing of Yemen. If the Saudis had to do it without our tankers, the level of bombing would be enormously reduced, probably by a factor of three,” former Pentagon official Pierre Sprey told HuffPost.

Tanks of U.S. fuel for the coalition’s jets could be moved out of the area in a handful of hours, the defense analyst estimated.

Without U.S. refueling in the air to the Saudis and coalition allies such as the United Arab Emirates, Morocco and others, the coalition would have significantly less time over Yemen and its jets could carry far fewer bombs. Sprey, who helped design and launch the F-16 and A-10 jets in the 1970s, estimated that the Saudis’ F-15 jets would have five to 15 minutes over the closest rebel territory if they were flying from a base in southwest Saudi Arabia, near Yemen. Were they to target rebel-held cities along Yemen’s southwestern coast, they would have only five minutes in the air. And if the Saudis choose to fly most sorties from a base farther from Yemen — and therefore less vulnerable to rebel attacks — they would have to make even shorter bombing runs, the analyst said.

Nations working with the Saudis choose whether to base their jets in the kingdom or at their own home bases. For those that fly from home because they are relatively nearby, like the UAE, U.S. aerial refueling is critical, Sprey said ― which means the coalition would have to rethink its ranks and would likely fly fewer planes for some time.

Right now, the analyst estimated that U.S. support means each coalition mission can carry up to six bomb units or cluster bombs, munitions widely banned by most countries other than the U.S. and Saudi Arabia, and fly for between one and three hours.

“Without the refueling, they certainly couldn’t carry on a campaign on this scale,” Hartung, the arms trade expert, said.

ABDULJABBAR ZEYAD / Reuters The Saudi-led coalition has bombed multiple facilities operated by the medical charity Doctors Without Borders, prompting the group to shut down some of its operations -- and leaving Yemenis with even less medical assistance.

The next step would be to pull U.S. personnel who are currently assisting the coalition. The Obama administration already reduced the number of Americans aiding the Saudi-led coalition to under five in June, the defense official said, following an attempt at a ceasefire in the spring. Though the ceasefire faced problems almost immediately and has now fully collapsed, the U.S. believes that the group of fewer than five Americans is still enough to meet the coalition’s needs, the official told HuffPost.

Were the president to fully shut down that joint cell, the coalition might cause more civilian casualties in the short run, Sprey said. But its general capacity to pick out targets would be more limited and the perception of a strong U.S. hand behind the war could start to recede ― granting the U.S. more legitimacy in its calls to strike more carefully, reduce the violence and ultimately move toward peace.

To better limit the Saudis’ capacity, the administration could also review the kingdom’s contracts with former U.S. military personnel now working as contractors and try to reduce private assistance to the campaign, Sprey suggested.

A final move for Obama would be to put conditions on future arms sales to the Saudis and their partners in the controversial coalition.

The president has sold more weapons to the kingdom than any previous holder of the Oval Office. He presents this as a key part of his Middle East strategy ― a way to reassure the Saudis while he has pursued successful nuclear diplomacy with their archrival, Iran.

However, Obama’s approach seems to have only enabled Saudi aggression by making the kingdom paranoid about abandonment by the U.S., encouraging it to deal with its own problems however it chooses (U.S. and international standards be damned) and providing it with the most advanced weaponry in the world.

Rights advocates say Obama or a future president should leverage the weapons deals to which the Saudis and the U.S. seem so committed.

Shocked by the reports out of Yemen, lawmakers who have a chance to approve or block Obama’s arms sales to Saudi Arabia seem more willing than before to use those deals to encourage changes in Saudi behavior, according to Cole Bockenfeld, deputy director on policy at the Project on Middle East Democracy. A recent effort in the Senate to vote down a deal providing the Saudis with fresh tanks was seen as “kind of a proxy vote to show some displeasure,” Bockenfeld said.

Kevin Lamarque / Reuters

The Obama administration could also take less drastic measures like preventing the flow of spare parts for U.S.-made machinery involved in the war, like the F-15 bombers, or suspending deliveries on existing contracts that have yet to be fulfilled.

Under U.S. law, credible reports of human rights abuses by the holders of U.S. weaponry require the executive branch to suspend security assistance until it can investigate whether international law has been violated, the American Bar Association pointed out in a recent letter that encouraged lawmakers to block the tank deal.

This means Congress also bears responsibility for the killing. It could pressure the Obama administration, if it chose, to take any of these measures and demand that the executive prove that the Saudi-led coalition is following international conflict standards before any more help of any kind is offered. Parliamentarians in London and Brussels for months have been putting pressure on their governments over the help Britain and European Union member states like France have been providing to the coalition.

Opponents of such actions to wind down the war have used the same arguments for the last 18 months: A U.S. role helps prevent even greater civilian casualties; the Saudis could become even more anxious and lash out more brutally if the U.S. failed to support them in a region that they consider their backyard.

That logic has less and less appeal on Capitol Hill, Bockenfeld said.

“I think we’ve turned the corner on that and are now looking at how complicit we want to be in this. The answer is as little as possible, while still telling the Saudis, ‘We’ve got your back,’” he said, describing the thinking among lawmakers and their staff. “Just compare how [the war] is going now to how it was going a year ago, when the U.S. was even more involved and we weren’t having the influence we should.”

Observers who say only the way to encourage a settlement to the conflict is to have a stake in the coalition have been proven wrong, Bockenfeld argued.

Of course, pulling the U.S. out of the war won’t end it entirely.

The rebel group fighting the Saudi-backed Yemeni government has proven that it’s willing to target civilians and commit major human rights violations as well, sometimes with arms provided by Saudi nemesis Iran.

That group, the Houthis, and its ally, former Yemeni president Ali Abdullah Saleh, may become emboldened if the U.S. backs away. They could launch fresh offensives against the parts of the country that the Saudi-led coalition is defending.

Meanwhile, the kingdom has shown no desire to back down or even accept greater accountability for its actions in Yemen. Asked how Saudi decision-makers would react to an Obama administration turnaround, Gulf politics expert Bilal Saab said it would be perceived as a stab in the back.

“The Saudis are determined to gain further leverage through battlefield advances,” the Atlantic Council scholar told HuffPost Wednesday in an email. “Don’t rule out a limited ground invasion.”

Still, ending U.S. cooperation with the Saudis’ misadventure in Yemen could help on three big fronts: by reducing the scale of the violence; by reducing the risk that U.S. complicity in the killing will spur greater anti-Americanism in the region; and by moving the situation toward what Saudi expert Greg Gause of Texas A&M University has suggested ― using American “influence over Saudi Arabia to help it find an exit ramp” out of an unpopular war.

But that all depends on whether the president wants to stop the slaughter. Right now, it certainly seems like he doesn’t.

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