Conservatives and libertarians can rejoice, if they wish, at the spectacle of Barack Obama proving once again — and perhaps more definitively than ever — that he is the worst president of the modern era, through his utter mishandling of the Syrian situation.

But they ought to wipe the smirks off their faces, because here’s the bitter truth: The GOP bench — the right-wing or even center right-wing presidents in waiting — isn’t a helluva lot better. Not enough, anyway.

At no time in our history, at least in my increasingly long lifetime, has there been such a dearth of key political leadership in our country on both sides of the ideological divide — and at a moment when the world seems about to explode.

Much as they have a great deal to recommend domestically, I’m sorry but Ted Cruz and Rand Paul — the leading “conservatarian” lights of the Senate — do not seem prepared to deal with Syria, Egypt, Iran, Pakistan, Yemen, Hezbollah, Hamas, al-Qaeda, North Korea, and, of course, Russia and China.

It is not enough to roll up the libertarian gangplanks and let the insane of the world blow each other up. That policy rarely works. It certainly didn’t in the 1930s. The insane of the world have a way of coming back to bite you. They’re doing their best at this very moment.

This is a sad Labor Day. America needs serious leadership and it doesn’t have it. Say what you want about this country, about its mistakes and its flaws, but a Pax Americana has prevailed since World War II. And that Pax has been a great positive for humanity. The Obama era seems to be ending it.

And the leadership pool does not look capable of recovering it. No Reagans are in the offing.

On the Democratic side we have the addle-brained Biden and the dishonest, selfish Hillary.

On the Republican side… who?

No one of real stature.