Cambodian Prime Minister Hun Sen. (Tang Chhin Sothy/AFP/Getty Images)

LAST WEEK, Cambodian opposition leader Kem Sokha was awarded the Asian Human Rights Peace Prize for his commitment to democracy. He was unable to accept the award — because he was languishing in jail, imprisoned by Cambodia’s authoritarian prime minister, Hun Sen, on far-fetched charges of treason. His arrest in September sounded the death knell for the first viable challenge to Hun Sen’s rule since the strongman came to power in 1985. As the country gears up for general elections in July, Hun Sen is set to become one of the world’s longest-serving autocrats. Yet, for the most part, the international community has watched Cambodia’s descent into despotism in silence.

Hun Sen’s government has a long record of engaging in arbitrary arrests, police intimidation and, in some cases, politically motivated killings. But its attempts to undercut democracy in Cambodia have picked up speed in the past year, apparently in anticipation of the July elections. It dissolved the Cambodia National Rescue Party, the country’s main opposition, and arrested party leader Kem Sokha. The government then forced the Cambodia Daily newspaper to shut down and ordered local FM stations to stop carrying the fair-minded broadcasters Radio Free Asia and Voice of America. Coupled with his continued persecution of human rights defenders, Hun Sen has managed to decimate Cambodia’s political opposition, independent media and civil society. His government may have invited 50,000 international observers into Cambodia to monitor the elections, but without functional democratic institutions, the upcoming vote will be little more than a farce.

The White House rebuked Hun Sen in November but has otherwise done little to support democratic values in Cambodia. It is time for the United States to do more. Congress is considering a bill that restricts U.S. military support to Cambodia and instructs the State and Treasury departments to take action against “individuals involved in undermining democracy in Cambodia.” These are important measures. The Trump administration has another avenue to deal a blow to Hun Sen’s government, too. The Global Magnitsky Act, passed by Congress in 2016, allows the president to impose sanctions on individuals who are responsible for grave human rights abuses. There are many in Hun Sen’s regime who fit this description.

The Trump administration has imposed sanctions on Hing Bun Hieng, the commander of Hun Sen’s bodyguard unit, who was implicated in violence against unarmed civilians and protesters. Now, a new Human Rights Watch report identifies 12 other senior security force officers who were involved in documented human rights violations. The list includes generals such as Kun Kim, a former Khmer Rouge officer who was linked to the arbitrary arrests of opposition party members, and Neth Savoeun, a police commissioner whose forces reportedly attacked and killed protesters in 2013.

It might be too late to uphold democratic principles in the upcoming election, but the United States should act to save what little remains of Cambodia’s democratic institutions and processes. Targeting Hun Sen’s generals — who are linchpins of his repressive rule — is a good place to start.