Trump just threatened to increase the U.S. nuclear arsenal:

President Donald Trump told reporters Monday that the United States would increase its nuclear arsenal until other nations “come to their senses,” threatening an arms race days after he said he would withdraw the US from a Cold War nuclear treaty.

“Until people come to their senses, we will build it up,” Trump said from outside the White House.

The U.S. doesn’t need to build more nuclear weapons, and increasing the arsenal will not make America or the world the slightest bit safer. On the contrary, a new nuclear arms buildup would cause other nuclear weapons powers to increase their own arsenals. Building more nukes would be extremely expensive, and it would make the world less secure by heightening international tensions, casting aside decades of arms control and arms reduction work, and encouraging more states to develop nuclear weapons for their own protection. This wouldn’t cause other governments to “come to their senses,” but it would show the world that our government has completely lost its own.

Trump seems to think that other states will be intimidated by a new buildup of nuclear weapons, but it is much more likely that they will be terrified into responding in kind. There is no way that the U.S. will be able to make any progress with North Korea if our government is simultaneously developing new kinds of nuclear weapons and increasing the number of weapons that it possesses. Other would-be proliferators may take this as a cue to pursue their own weapons programs. If reneging on the JCPOA was a body blow to the cause of nonproliferation, a new arms race could prove to be a fatal blow.

The cost of what Trump is proposing would be exorbitant at a time when the U.S. already spends far too much on the military. There could nothing more senseless and gratuitously militaristic than expanding a nuclear arsenal for its own sake. The U.S. needs to be be building on the successes of existing arms control agreements to get the world’s largest nuclear weapons states to cut back on their arsenals. It won’t be able to do that if it is throwing countless billions of dollars down a black hole of wasteful spending on new weapons that the U.S. doesn’t need.