Ripples of reform from Riyadh have been attracting positive press for the Saudis in Washington. The government recently pledged to permit women to drive, allow movie theaters into the country and to teach physical education to girls in schools. These are important steps, especially for gender equality. This month, Saudi Arabia’s Crown Prince Mohammed bin Salman, who has gotten credit for many of these reforms, ended up winning Time Magazine readers’ poll for Person of the Year.

But, in celebrating these moves, many seem happy to gloss over the young prince’s more problematic track record. Prince Bin Salman’s surprising decision to detain elites at five-star hotels in Riyadh on allegations of corruption apparently without due process, demands more scrutiny. So does his responsibility for the ongoing humanitarian catastrophe in neighboring Yemen.

The war in Yemen, and Prince Bin Salman’s prominent role in it as defense minister, fits poorly into a narrative of a visionary young reform-oriented leader. Since March 2015, Saudi Arabia has led a coalition of Arab countries against the Houthi armed group, which controls much of Yemen. There has been nothing bold or transformative about his coalition’s relentless bombing of Yemen’s civilians while denying to hold any of his own forces accountable for their war crimes. As restrictions on imports push millions of Yemenis further into famine and aid the spread of normally treatable diseases, Prince Bin Salman shouldn’t be getting a free pass. Instead, he and other senior coalition leaders should face international sanctions.

Imposing targeted sanctions for the indiscriminate bombing and unlawful blockading of essential goods to Yemen’s civilian population is well within the U.N. Security Council’s mandate. The council passed a resolution back in 2015 that gave it the power to place travel bans and asset freezes on anyone responsible for obstructing the delivery of life-saving aid. It has the power to put sanctions on anyone violating the laws of war in Yemen. Coalition leaders, including Prince bin Salman, meet that threshold.

In a world experiencing countless disasters, Yemen holds the ignominious place of having the world’s largest humanitarian crisis and worst cholera epidemic. Even before the Saudi-led military campaign, Yemen was the Middle East’s poorest country. Now, the United Nations is warning that Yemen is “on the cusp of one of the largest famines in modern times.”

The coalition justifies these restrictions by pointing to Houthi-Saleh forces’ use of a ballistic missile in November allegedly smuggled in from Iran. The Saudis say they downed another Houthi-fired missile directed to Riyadh today. U.S. Ambassador to the United Nations Nikki Haley recently stood in front of a display of missile fragments that she called “concrete evidence” of Iran’s “hostile actions.” Iran denies the claim. Setting aside the origin of the weapon, it’s true that a Houthi attack in November directed at Riyadh’s international airport was indiscriminate and a likely war crime. But while the laws of war allow blockades as a military tactic, they don’t permit restrictions that have a disproportionate impact on civilians.

But so far, the United Nations has taken a lopsided approach to Yemen’s conflict. The Security Council imposed travel bans and asset freezes on Houthi leaders responsible for abuses and on their erstwhile ally Saleh. The United Nations has information that points to the need for similar individual sanctions on coalition members, including military leaders in the United Arab Emirates and Saudi Arabia. But mostly because of the power of Saudi Arabia’s allies — the United States, France and the United Kingdom — the Security Council hasn’t acted. Despite the worsening humanitarian situation, it’s been six months since the council said anything on Yemen, emboldening the coalition on its destructive path.

The United States has supported the coalition, militarily and diplomatically. In a policy that dates back to the Obama administration, U.S. forces refuel coalition planes on bombing runs. Earlier this month, President Trump made a first move toward addressing coalition abuses with  two White House statements publicly calling on the Saudis to allow life-saving food, fuel, medicines and goods into Yemen.

As the defense minister of the nation leading the coalition, Prince bin Salman should shoulder responsibility for the coalition’s violations of international law. Trump set the tone with his early December White House statements asking the Saudis to change course. But they haven’t. Now he should put a threat into the mix by directing Haley to begin a conversation in New York around sanctions on coalition leaders. Some may see this as a long shot, but it’s the right thing to do. Moreover, the international tide is turning — even the British government is now openly suggesting that the Saudi coalition’s continuing restrictions on essential goods are in breach of international humanitarian law.

Continuing to shield the Saudis will abandon millions of Yemenis to further death and misery. The Crown Prince shouldn’t be able to paper over abuses abroad with talk of reform at home.