Despite the imposition of unprecedented sanctions against Russia by the Trump administration and Congress over the past year, President Vladimir Putin only seems more intent on causing grievous harm to international peace and stability.

Alongside increased financial sanctions against Mr. Putin and his cronies, there is another arrow in the American quiver that would add diplomatic pressure against Russia: The State Department should consider adding the country to its list of state sponsors of terrorism, alongside its close allies Iran and Syria.

The moral case for such a designation is sound. Russia has invaded its neighbors Georgia and Ukraine, it supports the murderous regime of Bashar al-Assad and our enemies in Afghanistan, and it is engaged in active information warfare against Western democracies, including meddling in the 2016 United States elections.

This week, the Organization for Prevention of Chemical Weapons announced that the Kremlin had crossed yet another previously unimaginable line, when it confirmed findings by the British government that a Russian military-grade nerve agent, which British authorities identified as Novichok, was used to poison a former Russian intelligence agent, Sergei Skripal, and his daughter in the English city of Salisbury. The attack also resulted in the hospitalization of British law enforcement officials who responded to the scene, as well as bystanders.