On Friday’s broadcast of HBO’s Real Time, host Bill Maher sounded a little like—forgive me—Pat Buchanan.

Discussing immigration and multiculturalism in America with guests Jon Meacham and Fareed Zakaria, Maher said immigration was a topic “worthy of debate,” particularly since the United States has had difficulty assimilating immigrants in recent decades.

“One of the first things I said on my old show (ABC’s Politically Incorrect) is if you’re going to come to the melting pot, melt a little bit. You’ve got to melt a little,” Maher said. “You can’t take a driver’s license photo in a burqa. We have to see your face.”

The line got a laugh from Maher’s audience, but the discussion as a whole was a serious one and touched on some important cultural and political issues.  

The dialogue stems from a column Zakaria wrote on Aug. 3 that said “Democrats should rethink their immigration absolutism.” In the column, Zakaria said Americans agree with Democrats on many important political questions but believe the party is out of touch on immigration.

And they are right. Consider the facts. Legal immigration in the United States has expanded dramatically over the last five decades. In 1970, 4.7 percent of the U.S. population was foreign-born. Today, it’s 13.4 percent. That’s a large shift, and it’s natural that it has caused some anxiety.

The anxiety is about more than jobs. In his 2004 book “Who Are We?,” Harvard University scholar Samuel Huntington pointed out that the scale, speed and concentration of Mexican migration into America after 1965 were without precedent in the country’s history and could provoke a backlash.

He asserted that America had more than just a founding ideology; it had a culture that had shaped it powerfully. “Would America be the America it is today if in the seventeenth and eighteenth centuries it had been settled not by British Protestants but by French, Spanish, or Portuguese Catholics?” Huntington asked. “The answer is no. It would not be America; it would be Quebec, Mexico, or Brazil.” He advocated some modest limits on immigration and, more important, a greater emphasis on assimilation.

Maher appeared to agree with Zakaria. He said the Democratic policy on immigration has essentially become “come one, come all” because “they live in this cult of celebrating diversity.”

These are tough words from a staunch liberal, and I suspect Maher may be disinvited from a couple of Hollywood dinner parties for using the words “cult” and “diversity” in the same sentence. But Maher made it pretty clear he’s tired of being called a bigot (and worse) for suggesting that curbing immigration is an appropriate topic of discussion.

“If we ask questions about Muslim immigration… it has to just be a racist reason for that,” Maher said. “First of all, it’s not a race, it’s a religion. But we’re talking about those shared values.”

Maher is talking about a culture of “shared values,” but what if a nation no longer believes its values are worthy of sharing? Or what if people view attempts to assimilate immigrants as cultural colonialism?

I think many Americans (and probably Maher) would struggle to effectively answer these questions. But assimilation is an important part of the immigration process, Zakaria pointed out.  

“I can say as an immigrant, if I wanted to maintain Indian culture I could’ve stayed in India,” he says. “The reason I came to America is because I admired American principles.”

Thomas Jefferson, were he alive today, would concur with Zakaria.

“Born in other countries, yet believing you could be happy in this, our laws acknowledge, as they should do, your right to join us in society, conforming, as I doubt not you will do, to our established rules,” he wrote in 1801. “That these rules shall be as equal as prudential considerations will admit, will certainly be the aim of our legislatures, general and particular.”

The fact that Maher and Zakaria, two prominent progressives, see this is important. It shows that one need not be a culture warrior to understand that culture matters, and that preserving and sharing American principles should be part of our immigration policy.