President Obama addressed the topic of nuclear arms today in Prague, Czech Republic, a subject which has gained new urgency in the world since North Korea launched a missile last night. The president talked quite a bit about “moral responsibilities” in trying to seize the high ground.

Shifting on an eight-day European trip from the economic crisis to the war in Afghanistan and now nuclear capabilities, Obama said his goal of “a world without nuclear weapons” won’t be reached soon, “perhaps not in my lifetime.”

But he said the United States, with one of the world’s largest arsenals and the only nation to have used an atomic bomb, has a “moral responsibility” to start taking steps now.

It is not only a lofty goal. Gary Samore, Obama’s arms control coordinator, said the plan has a strategic aim: to give the U.S. extra leverage in opposing the pursuit of nuclear arms in adversarial countries such as North Korea and Iran. “We are trying to seek the moral high ground,” Samore said.

As if we needed another reminder of why the eight years have been so disastrous. President Obama now has to accuse North Korea of “breaking rules” less than a decade after the United States attacked a sovereign nation on fabricated intelligence and tortured prisoners of war, with both acts violating international law. Yes, this is a test for the president.

Is there any doubt that what he’s saying needs to be said? Absolutely not. If we’re looking for an issue that strikes at the heart of the common good, this is it. Everyone is threatened here.

The next move falls to the UN Security Council, but with China, the closest thing North Korea has to an ally, possessing veto power, that could prove problematic.