Just three years ago, President Obama famously ridiculed GOP opponent Mitt Romney’s statement that Russia remained America’s main geopolitical foe by taunting: “The 1980s are calling to ask for their foreign policy back.”

Four years before that, Obama stood at Berlin’s Brandenburg Gate to declare that once he became president, all people would join him around a global campfire, hold hands and put an end to the world’s evils and miseries.

Well, seven years into Obama’s presidency, the promised worldwide Kumbaya is instead global chaos — caused in large measure by his willful retreat from America’s position of leadership.

Washington’s traditional allies increasingly feel abandoned, its enemies emboldened. The United States isn’t even leading from behind — it’s cowering in weakness.

And no one is taking better advantage of this than Vladimir Putin, now storming headlong into the yawning chasm of American retreat and reasserting Russia’s global influence and power — just as Mitt Romney said.

Putin remains unchallenged in his invasion of Ukraine, leaving him free to intervene — again unchallenged — in the Middle East.

In Syria, Iraq, Afghanistan and Libya, Obama’s outreach to the Muslim world hasn’t ended the threat of terrorism. On the contrary, it has seen the rise of “JV team” ISIS and new power for the Taliban. Israelis and Palestinians remain as far apart as ever — because only Israel has been targeted to make concessions.

This president accuses his political foes of wanting to wage war as their first option and warns of the limits of unilateral military power.

But in his eagerness to leave office as the president who ended America’s wars, he refuses to consider any use (or even a credible threat) of US force — even when hundreds of thousands are being massacred in Syria, many by the chemical weapons he claimed to eliminate.

His premature abandonment, against all military advice, of Iraq and Afghanistan (where the pullout is still under way) has left both countries worse off. Iraq, in particular, is bleeding far more than it did even in the worst years of “George Bush’s war.”

Equally eager to open America’s arms to longtime adversaries, this president has begun new relationships with Iran (all but giving Tehran a direct path to a nuclear arsenal) and Cuba without any concessions in return — even on such basic issues as human rights.

It’s no accident Obama has twice spoken in Berlin — at the very spot where Ronald Reagan famously demanded Mikhail Gorbachev “tear down this wall.” Two years later, the Berlin Wall came down. Two years after that, the Soviet bloc collapsed, ending the Cold War.

Obama chose Berlin as the place to call on all nations to join him in “tearing down the walls” to “remake the world.” But his soaring rhetoric was followed by indecision, hesitation and outright appeasement.

America’s allies are calling, Mr. President. They want Ronald Reagan’s assertive foreign policy of the 1980s back.

They want an America that leads — not retreats.