Abid Qureshi may be the next lightning rod in a tumultuous presidential campaign.

When President Obama named Mr. Qureshi to a federal judgeship on Tuesday, the first Muslim American to be nominated, he underscored a message about the importance of a diverse judiciary: by some counts, the president has done more than any of his predecessors to make the federal judiciary look like the United States, with record numbers of female, Latino, black, and gay judges in courts today.

But he may also have issued an unspoken challenge to Donald Trump, who has questioned whether he would be treated fairly by a Muslim judge, because of the Republican candidate's proposed ban on Muslim immigration.

That wasn't the only time Mr. Trump criticized a judge because of their ethnicity or religion. In June, he questioned the impartiality of US District Judge Gonzalo Curiel, a San Diego judge of Mexican descent who was presiding over a fraud case against the now-defunct Trump University, saying that his promise to build a wall between Mexico and the US made Judge Curiel's heritage "an inherent conflict of interest."

"[Obama] is baiting Trump to make an outlandish statement akin to [those against] Judge Curiel at the height of the campaign," says Chris Dolan, a professor of politics and global studies at Lebanon Valley College in Annville, Penn.

Born in Pakistan and educated at Cornell University and Harvard Law School, Qureshi is a partner at the Washington, D.C.-based law firm Latham & Watkins LLP. He has been chosen to fill a spot on the US District Court for the District of Columbia, one of the most influential seats in the country.

But his confirmation could be a long shot. As Obama’s term winds down, Senate Republicans have stopped confirming his judicial picks, including Merrick Garland, Obama's nominee to the Supreme Court. So far, the Senate has refused to hold hearings on Mr. Garland's nomination.

Nonetheless, Qureshi's nomination is a symbolic and likely a deliberately timed announcement, particularly in an election cycle in which Trump has stoked fears about the loyalty and patriotism of Muslims. Considering the bruising Trump took in July, following his criticism of Khizr Khan, the father of a fallen Muslim soldier who spoke at the Democratic National Convention, the Republican candidate will need to tread carefully around Qureshi's nomination.

"The president is ... putting Republicans in the Senate, particularly those who are up for reelection and vulnerable, in a defensive posture. They will have to respond to this nomination. Moreover, Donald Trump will also have to respond," says Natalie Davis, a professor of political science at Birmingham-Southern College in Alabama.

"There is some risk in this. Obviously, the president made a calculation. His hope is that ... he can force Republicans to look bad in their opposition," Professor Davis adds.

Of course, Trump hasn't exactly made nice with Muslims during his presidential campaign. He's proposed banning Muslims from traveling to the US, said mosques should be under surveillance, criticized the family of a slain Muslim solider, and once said it was "absolutely" possible that he would be treated unfairly by a Muslim judge.

Some advocates of judicial diversity view Trump as a threat to their cause.

“It’s incredibly troubling. It would be a major step backwards in the work done to diversify the judiciary to reflect the nation they represent," Vincent Eng, a Washington lobbyist, told the Guardian in June, after the Republican candidate's remarks about Muslim judges.

As such, Obama's announcement may put Trump in a difficult position, while boosting Hillary Clinton, says Whitney Ross Manzo, an assistant professor of political science at Meredith College in Raleigh, N.C.

"Opinion polls showed that Americans heavily disagreed with Trump's remarks about Judge Gonzalo Curiel, so Trump should steer carefully when talking about this nomination," says Professor Manzo. "Obama's move here helps Clinton, as it demonstrates a Democratic commitment to a diverse bench, which many Americans value."

However, Qureshi's nomination may be just one more milestone in the president's legacy of appointing judges who reflect the country's growing diversity.

Going by his nominations, the president has done more than any of his predecessors to make the judiciary more representative of its country: about 43 percent of his nominees have been women, and 36 percent are people of color, according to The Guardian, which reports there are more female, black, Latino, and gay judges than ever before. Among the 3,000 federal judges currently serving in the US judiciary, however, not a single one is Muslim – which makes Qureshi's nomination historic, as well as profoundly political.

Qureshi's nomination marks a new milestone in judicial diversity for the Obama administration, says Nan Aron, President of Alliance for Justice, a liberal advocacy group that monitors judicial appointments. "The President has always made diversity a centerpiece of his judicial selection, long before Donald Trump arrived on the scene," Ms. Aron says.

The timing of this announcement may be simply coincidental, cautions Aron, who says President Obama has championed judicial diversity for years and was considering Qureshi long before Trump emerged as the GOP nominee.

"President Obama has made it clear that he believes a diverse judiciary, one that reflects all types of Americans, is important for the just administration of law," explains Manzo. "As he said in his remarks nominating Sonia Sotomayor, Obama thinks that lived experience is key for understanding how real Americans live their lives."

Nominating a Muslim judge is one more "signal that he believes judging is not just about unbiased interpretation of the law or a brilliant legal mind ... but also about using one's own experience to inform decisions," she says. Clearly, she adds, the president is aware that Qureshi might never be confirmed, but "he obviously thinks the signal itself is just as important."