U.S. Sen. Tom Cotton, R-Ark., thinks it’s OK to travel abroad and to meet with a foreign head of government for the purpose of undermining a key foreign policy initiative.

It’s not OK. At least it’s never been acceptable … apparently until now in some circles.

Cotton went to Israel and Is meeting with Israeli Prime Minister Benjamin Netanyahu to figure out a way to torpedo the Iran nuclear deal brokered by the United States and five other great powers.

Cotton’s meeting with Netanyahu now has become the norm, it seems, for critics of President Obama. They forget what they said when then-Speaker Nancy Pelosi traveled to Syria to meet with dictator Bashar al-Assad. Vice President Dick Cheney reminded us then that only the president can conduct foreign policy.

Except that Pelosi coordinated her visit with Bush administration officials and had made sure she didn’t interfere with what President Bush’s goals were as they regarded U.S. policy toward Assad.

Cotton said: “Today’s meeting only reaffirms my opposition to this deal. I will stand with Prime Minister Netanyahu and Israel and work with my colleagues in Congress to stop this deal and to ensure that Israel has the means to defend itself against Iran and its terrorist surrogates.”

We’ve only got one president of the United States at a time. And at this moment, it isn’t Tom Cotton.