That friendly fist bump with Saudi Crown Prince Mohammed bin Salman might not have been such a defining moment — had Biden not first set himself up.

During the 2020 campaign, Biden said that when he encounters the prince, he would treat him like the “pariah” he was for having authorized the murder and dismemberment of Washington Post columnist Jamal Khashoggi.

As for Biden’s depiction of how he confronted MBS behind closed doors, the Saudis dispute his rendition, and many of his own countrymen disbelieve Biden.

Why? Because Joe Biden has a history of painting himself as heroic in personal encounters where few contemporaries recall him that way.

The classic is the story Biden has often told of confronting, as a pool security guard in a Black neighborhood, a gang leader named Corn Pop, whom Biden ordered out of the pool for breaking the rules.

When Biden left for the day, Corn Pop was waiting for him, with three gang members, and holding a straight razor. Biden, holding a six-foot length of chain, he says, faced him down, and Corn Pop backed off.

Whatever the reality of that event, 60 years ago, Biden has issued, in his 18 months in office, a remarkable number of warnings and threats as to what he would do as commander in chief if challenged, thereby putting his own and his country’s credibility on the line.

Asked, before his trip to the Middle East, if he would use force to prevent Iran from acquiring nuclear weapons, Biden replied, “If that was the last resort, yes.”

During the trip, the U.S. and Israel signed a joint pledge to deny nuclear arms to Iran. We are now committed.

Given that the U.S. has fought in five wars in the Middle East in this century — Afghanistan, Iraq, Syria, Libya, Yemen — one would think this country would be wary of committing itself to a new war with one of the largest powers in the region.

When Russian President Vladimir Putin built up forces outside Ukraine and asked repeatedly for assurances that Ukraine would not be brought into NATO, an alliance aimed at Russia, the Biden administration refused.

The February invasion followed, and among Biden’s subsequent threats, his call for the removal of Putin was virtually declared a war aim.

“For God’s sake, this man cannot remain in power,” thundered Biden in Poland, a declaration that was hastily walked back by White House staff.

In addition to the weaponry we were shipping to Ukraine — long-range artillery and rockets — Biden announced at the NATO summit in Madrid that the U.S. would be strengthening its military presence in Europe.