It seems that what goes around does indeed come around. That is a lesson that has become painfully clear to the right-wing zealotry of the Republican Party, courtesy of Texas Sen. Ted Cruz.

The lesson starts with President Barack Obama. Even before Inauguration Day 2009, the Republican right attacked the very legitimacy of the Obama presidency, claiming that there was no evidence that he was born in the United States. So intense and widespread were the questions and criticism that these radical conservatives soon had a name for their movement. Soon, the so-called “birthers” unleashed a barrage of denigration of the nation’s 44th president.

To most reasonable minds, the questioning of Obama’s legitimacy was steeped in poorly veiled racism. It was the handiwork of far-right critics who somehow couldn’t quite stomach the fact that the nation was being led by its first African-American president. The repulsion was—and continues to be—far from hidden. It comes through in everything, from slights to outlandish behavior and bizarre statements from elected officials.

The birther champion and lead spokesman was Donald Trump, the business tycoon whose cravings for media attention are as legendary as they are insatiable. The president produced his birth certificate, and its legitimacy was verified by all possible government officials in Hawaii. Nonetheless, Trump made it nearly a full-time job not only to challenge Obama’s birth in the United States, but also to assault the president’s legitimacy and patriotism.

It is a theme that has become most common. It was put bluntly by Mike Coffman, a Republican congressman from Colorado, who said that Obama was “just not an American.” The most recent musing of that sort has come from Maine’s tempestuous Republican governor, Paul LePage, who was reported to have told guests at a private fundraiser that Obama “hates white people.”

But now, the birther shoe is on the other foot. Cruz, the darling of the right-wing tea party set, has indicated his own aspirations to someday win the White House. However, Cruz, unlike Obama, was not born in the United States. Instead, he was born in Canada to an American mother and a Cuban father. It was recently made public that the Texas senator holds dual citizenship and is both Canadian and American (he has since renounced his Canadian citizenship).

Somehow, all the birther zealots are now saying little in questioning the fitness for the presidency of their right-wing colleague. Trump, for example, has been uncharacteristically subdued on the topic of Cruz’s citizenship. “I don’t know the circumstances. I heard somebody told me he was born in Canada. That’s really his thing,” Trump said, speaking to ABC News.

Despite the irony created by the two birth discussions, there are some strong differences. Unlike Cruz, Obama was born in the United States but was beset by a group of critics who were intent on branding him as an illegitimate usurper. Cruz’s birth outside the United States is not in dispute, but there is clearly no question among the right of his credentials to lead.

Perhaps the Cruz episode will make clear to the Obama birther crowd how outlandish their ravings have been regarding Obama. It’s time for the right to elevate its tone, to act with civility and to treat the president of the United States with the standing his position demands.