Since the early days of his presidency, Saudi Arabia has aggressively courted Donald Trump’s affections. The kingdom rolled out the carpet for Trump’s state visit to Riyadh, where officials projected Trump’s face onto buildings and showered him with exorbitant gifts. And while the United States has long adopted a laissez-faire view toward Saudi Arabia’s belligerence in the region, no recent president has been as openly enamored of the nation and its rulers as Trump.

Trump has made his support of Saudi Arabia and other Arab states the centerpiece of his foreign policy, going so far as to publicly trample his own secretary of state to support the kingdom in its dispute with the Iran-friendly Qatar. And when it comes to Saudi Arabia, there is no greater gift than supporting the country in its battle for regional influence with Iran—a cause the Trump administration has taken up with gusto, constantly lambasting Barack Obama for its signing of the 2015 Joint Comprehensive Plan of Action, more popularly known as the Iran nuclear deal.

So, it should come as little surprise, then, that Trump on Friday craftily outraged Iranians from Tehran to Los Angeles. In justifying his decision to withdraw presidential certification for the Iranian nuclear deal, Trump said Iran’s regime “harasses American ships and threatens freedom of navigation in the Arabian Gulf and in the Red Sea.”

“Arabian Gulf”?

The two words likely didn’t raise too many eyebrows among the American public, but they landed like a rhetorical bomb among Iranians, who immediately took to Twitter to browbeat the president for misidentifying the Persian Gulf, the body of water that separates Iran’s southwestern coast and the Arabian Peninsula.

And while the consequences of Trump’s risky bet on the Iran Deal are more significant than a semantic difference, Iranians—who take great pride in their history in the region—did not let the lexical slight, Freudian or otherwise, go unnoticed. Renaming the Persian Gulf might be the most efficient way to unite the global Iranian diaspora.

Many took to Twitter to protest Trump’s phrasing, and some 1.4 million people commented on Trump’s Instagram post regarding his Iran strategy—many times more than the thousands or tens of thousands of comments he normally receives.

Most of the world uses the “Persian Gulf” designation, and has for most of recorded human history. The name was first coined in the fifth century B.C., by the Persian king, Darioush. The United States officially refers to the body of water as the Persian Gulf, as does the United Nations.