In general, the children of public figures are off-limits. But with the recent remarks from Tanner Flake, son of Sen. Jeff Flake (R–Arizona), it’s worth relaxing that rule for a moment.

First, the details. On Wednesday, BuzzFeed’s John Stanton uncovered the Twitter feed of Senator Flake’s 15-year-old, Tanner, who used the social-networking service to threaten the “faggot” who stole his bike and broadcast his scores in an online game, where he went by the moniker of “n1ggerkiller.” His comments on YouTube contained similar language, calling Mexicans the “scum of the earth.”

Senator Flake has issued an apology on behalf of his son, saying: “I’m very disappointed in my teenage son’s words, and I sincerely apologize for the insensitivity. This language is unacceptable, anywhere. Needless to say, I’ve already spoken with him about this, he has apologized, and I apologize as well.” There’s no reason to think that apology isn’t sincere or that Flake is somehow responsible for his son’s comments.

What we do know, however, is that when he was a member of the House, Flake represented, and lived in, an area that was overwhelmingly entirely white, 76.6 percent white, according to the latest release from the Census Bureau. In all likelihood, and like many other Americans, he lives a racially homogeneous personal and professional life.

For many people—including Senator Flake, I think—that doesn’t preclude an ability to see and empathize with the experiences of people with different racial, ethnic, and religious backgrounds. For others, it does, and Tanner Flake’s comments are what it looks like when homogeneity leads to isolation, lack of compassion, and a blinkered view of the world.

That may be worth noting because it’s also a fair diagnosis—and explanation—of what’s happening in the Republican Party. Over the last year, we’ve seen a parade of Republican lawmakers, activists, and donors who can’t seem to avoid offensive language. If it’s not Rep. Trent Franks (R–Arizona), who claimed that the rate of pregnancies from rape is “very low,” despite reams of proof to the contrary, then it’s a GOP official in Kansas who casually refers to “n----r rigging” a home, or an Alaska congressman who uses the term “wetbacks” to refer to Hispanic migrant workers.

Indeed, it’s not at all hard to assemble a long list of these remarks (and subsequent apologies). On Wednesday, for instance, Rep. Steve King (R–Iowa) complained that “illegal aliens have invaded my D.C. office,” after a group of young immigrant activists came to protest his immigration stance. Even if you oppose comprehensive immigration reform, there’s no reason to reach for dehumanizing language.

My hunch is that the insensitive comments on sexual assault and racial slurs are a product of the GOP’s overwhelming homogeneity. It’s a political party dominated by a single demographic of people: older whites, with middle to high incomes, socially conservative beliefs, and a deep attachment to the America of the past. And more important, until the last five years the demographic has been a reliable source of election victories. While Democrats have had to build relationships with diverse communities of people to create a national majority, or something close to it, Republicans have been able to rely on their advantage with the American “mainstream” to win elections and hold power.

The mainstream is changing, but for all the talk of outreach and messaging, Republicans haven’t made an effort to change with it. Instead, the GOP has cloistered itself among its supporters, with an entire branch of the party—its congressional wing, more or less—operating in its own reality, where President Obama is an unpopular tyrant, his policies are bound to fail, and the public is eager to see Republicans return to prominence. This despite the GOP’s abysmally low approval rating among a large majority of Americans and Obama’s continued popularity.

In much the same way that a closed world, online and off, almost certainly enabled Tanner Flake to say offensive things without reprimand, the GOP’s lack of diversity has left it in a place where there’s no one to shame its lawmakers into silence or reflection. There was no one to tell Rand Paul that he would be ill-served by giving a lesson in black history to students at Howard University, just as there was no one to tell Todd Akin that he should educate himself about rape before talking about it.

If Republicans need diversity, it’s so they can stop making stupid claims about other people’s experiences. And once they climb that hurdle, they’ll be better placed to appeal to new groups of voters and win their support. It’s why we should hope for success for politicians like South Carolina Sen. Tim Scott and Florida Sen. Marco Rubio. A Republican Party that recruits and promotes minorities and others is one that can potentially learn to talk to them. And a GOP that can talk to all Americans, and not just their narrow demographic slice, is good for the country.