President Obama has made nuclear nonproliferation one of his highest priorities but, as the Wall Street Journal explains, the White House’s weak response on Ukraine is sending all the wrong messages.

It’s worth recalling that when the Soviet Union collapsed, Ukraine was left with an enormous nuclear arsenal of 1,800 weapons, more than any other country at the time except for Russia and the United States. The Clinton administration was concerned that these warheads might get loose and convinced Kiev to sign on to the 1994 Budapest Memorandum on Security Assurances, with which Ukraine agreed to join the Nuclear Nonproliferation Treaty and send its nuclear arsenal to Russia—in exchange for security “assurances” from Russia, the U.S. and United Kingdom that included “promises to respect Ukraine’s independence and sovereignty within its existing borders, as well as refraining from threatening or using force against Ukraine.”