Some Democrats seem to feel a strange regret for the killing of a monster who specialized in killing Americans. The linguist his proxies killed on Dec. 27, Nawres Hamid, was merely his last victim out of more than 600 in Iraq since 2003. His forces have instigated attacks against our troops in Afghanistan. He plotted a (foiled) bombing in Washington, D.C., and attempted attacks on the soil of our European allies. He armed the terrorist group Hezbollah in Lebanon with rockets to pummel the Jewish state of Israel. And he was greeted moments before his death by a terrorist responsible for the bombing of our embassy in Kuwait in 1983.

Some of the president’s critics will concede that Mr. Suleimani was an evil man, but many complain his killing was unlawful. Wrong again. He was a United States-designated terrorist commander. As I have been briefed, he was plotting further attacks against Americans at the time of his death. The authority granted to the president under Article II of the Constitution provides ample legal basis for this strike. Furthermore, those who accept the constitutionality of the War Powers Act should recall that Congress’s 2001 and 2002 Authorizations for Use of Military Force very much remain in effect and clearly cover the Suleimani operation. This will be a relief to the Obama administration, which ordered hundreds of drone strikes using such a legal rationale.