To hear Barack Obama tell it, his career trajectory from backbencher in the Illinois state legislature to president of the United States has gone flawlessly. It’s everyone else who’s let him down.

Behold the Immaculate Administration — conceived in sinlessness and discharged with purity of heart. If only others would pull their load.

After all, it can’t be his fault that, seven years on, the economy is still a mess, the national debt is pushing $20 trillion, Russia is gobbling up bits of central Europe and his handling of the Middle East has sent a tidal wave of Muslim “refugees” streaming toward the heart of Europe while ISIS builds a caliphate, can it?

Case in point: Libya.

Obama made a great show of “leading from behind” when the 2009 Nobel Peace Prize winner ordered regime change there in concert with European allies.

Everything would have been just fine, but — wouldn’t you know it — those darn foreigners let the president down. As he told Jeffrey Goldberg in a far-ranging apologia in the Atlantic this month: “When I go back and I ask myself what went wrong, there’s room for criticism, because I had more faith in the Europeans, given Libya’s proximity, being invested in the follow-up.”

Obama bashed former French president Nicolas Sarkozy for glory-hogging, and blamed the Libyans for an excess of tribalism “greater than our analysts had expected.”

But he saved his greatest scorn for a “distracted” conservative British prime minister David Cameron who, Obama said, simply stopped paying attention, allowing Libya to become “a s – -t show.”

That undiplomatic but typical Obama wisecrack forced the White House to quickly scramble for its long-lost reset button, affirming through clenched teeth how much it “deeply values” America’s “close partner.”

It’s nice to see that two terms as president has not dented Obama’s unshakeable faith in himself.

Speaking of those eight years, Obama also disavowed any responsibility for the country’s increased polarization over that period.

Those things he naturally blames on the evil Republicans and a (largely imaginary) hostile media. Nor is he responsible for the unexpected rise and continuing appeal of Donald Trump, who embodies the manifest resentment of millions of Americans.

“It’s fair to say that the Republican political elites and many of the information outlets have been feeding the Republican base for the last seven years a notion that everything I do is to be opposed, that cooperation or compromise somehow is a betrayal,” he said in a Thursday news conference.

But as long as the president’s definition of “compromise” is “do it my way,” it’s hard to grasp the concept of legitimate opposition, much less a loyal opposition.

As the Immaculate Administration nears its end, this is perhaps the most valuable lesson it can bequeath to its successor: let him who is without sin cast the first stone.