It's a frequent refrain that President Trump's North Korean diplomacy is delusional — that by building a personal rapport with Kim Jong Un, Trump gives Kim greater space and time to manipulate him in North Korea's interests.

I think that's untrue.

But even if it is true, even if Trump's diplomacy is serving Kim more than it is serving America, it is at least offering the U.S. one useful thing. If diplomacy eventually fails, Trump will be able to make the unimpeachable case to the world that he went all out to reach a peaceful solution to the crisis.

The exhaustion of diplomatic alternatives to conflict is a standing expectation of just war. U.S. military strikes against North Korea's nuclear and ballistic missile programs might not spark major North Korean retaliation. But if war does follow, it will be brutal. Thousands, more likely tens of thousands will die. Trump's diplomatic efforts thus speak to the moral necessity of mitigating this risk.

Trump's exhaustive diplomacy would also help the U.S. to rally the world to its side in the event that military action is necessary. While few nations are likely to join any U.S. action against North Korea, Trump's efforts have not gone unnoticed in foreign capitals. Indeed, those efforts are widely regarded with great sympathy by foreign governments that otherwise dislike the president. So if his personal diplomacy fails, Trump will be more easily able to persuade foreign governments to support tougher sanctions against Pyongyang. Even if only marginally, his efforts will also lend greater international acceptance of last resort U.S. military action.

We must remember that diplomacy isn't about nice photos. It's about setting the ground, for good or bad, on what comes next. Either way, Trump's diplomatic efforts will set the groundwork positively for the Untied States.