Donald Trump might doom the Republican party. As he inches closer to the nomination, national polling suggests he is in a very weak position in the general election. A loss in November could leave the party in shambles, more divided than ever.

That's a big deal, but some right-of-center Trump skeptics are trying to talk themselves into the idea that he's only a temporary setback to the party.

RealClearPolitics' Sean Trende notes correctly that there is a long history of pundits over-reading single landslide elections and writing parties out of history, only to see them bounce back two or four — or even six — years later. Even a really bad 2016 election could be the just the same for the GOP. That may be right. But there's a chance that it could be wrong.

Just ask Pete Wilson, the former governor of California who managed to turn a contested state into a Democratic stronghold by over-indulging a shrinking white majority's fear of uncontrolled immigration and ending up defining his party as permanently unacceptable to the state's new diverse majority.

What happened in California should serve as a warning to future of the Republican party.

California used to be a swing state

Both Richard Nixon and Ronald Reagan were statewide elected officials before ascending to the presidency. From 1968 to 1988, the GOP carried California in every presidential election. It swung to the Democrats in 1992 as part of Bill Clinton's larger revival of the Democratic Party's national fortunes.

But in the 1990s California had a Republican governor, Wilson, who had served as the state's US senator for most of the 1980s. In the 1994 midterm elections, the GOP even swept into a majority in the state assembly.

Wilson and his Republican colleagues were closely associated with a law enacted via ballot initiative known as Proposition 187 that sought to create a state-run citizenship verification system and bar undocumented immigrants from accessing state services. It was, at the time, the very first effort to create a state-level immigration control policy, and it's no coincidence that the trend came first to California — the state had a lot of immigrants, residing there both legally and illegally. So many that the state was close to tipping over into "majority-minority" status, which surely heightened the salience of immigration-related concerns to the state's white conservatives.

Wilson was also a proponent of "tough on crime" policies and promoted a landmark "three strikes and you're out" law that greatly increased the state's prison population.

In other terms, however, he was a moderate Republican. Business-friendly, to be sure, but not a budget-cutting ideologue or a Bible-thumper.

Some issues are bigger than issues

But what makes Wilson remarkable is that he was also the last Republican to win a statewide election in California under anything resembling normal circumstances. Sure, Arnold Schwarzenegger sneaked into office in 2003 as part of an unusually structured recall election, and governed completely independently from the conservative movement.

Beyond that — nothing.

Not because Prop 187 became hideously unpopular per se, but because it became emblematic of the California Republican Party's transformation into a vehicle for white identity politics, a transformation that rendered the GOP unacceptable to a majority of the state's voters.

This message might best be taught by the RNC itself, in a post-mortem on the 2012 presidential election: Among Latinos, certain aspects of the immigration debate transcend the specifics of the policy argument (emphasis added):

If Hispanic Americans perceive that a GOP nominee or candidate does not want them in the United States (i.e. self-deportation), they will not pay attention to our next sentence. It does not matter what we say about education, jobs or the economy; if Hispanics think we do not want them here, they will close their ears to our policies. In the last election, Governor Romney received just 27 percent of the Hispanic vote. Other minority communities, including Asian and Pacific Islander Americans, also view the Party as unwelcoming. President Bush got 44 percent of the Asian vote in 2004; our presidential nominee received only 26 percent in 2012.

The message California's non-whites took from Wilson's approach in the 1990s was that Republicans didn't want them living there, and they have neither forgiven nor forgotten that message.

While Republicans continue to perform well in Latino-heavy states like Nevada and New Mexico, fielding Latino candidates for office while pushing low-tax and pro-business policies, they have only gotten weaker and weaker in California.

The real Trump risk: long-term alienation

This is the real risk Trump poses to the GOP. Not that he'll lose in a landslide so bad the party can't recover — Wilson didn't lose at all, and the party bounced back easily from a big defeat in 2008 — but that its brand will be more or less permanently tarnished in the eyes of many Americans.

After all, the message of the party of small government saying it wants to build a wall of unprecedented scale and then create a deportation force large enough to round up 11 million people is pretty unambiguous — he doesn't want people of Latin American ancestry living in the United States. Both Trump's trade policy and Trump's foreign policy seem grounded almost entirely on hostility to foreigners, and his rise to prominence as a figure in conservative politics is based entirely on his assertions that Barack Obama is not genuinely American.

Trump's campaign to "Make America Great Again" is transparently based on an effort to narrow the definition of who counts as an American. And while Republicans can easily shed specific policy stances that their likely 2016 nominee takes, if they stand shoulder to shoulder with Trump in a campaign whose main subject is whether non-white Americans count as genuinely American, that won't be forgotten.

Back in 1990, 57 percent of California's population was non-Hispanic white and it was a swing state. By 2000, they were a minority, and the state was solidly blue. In 2012, 63 percent of Americans overall were non-Hispanic whites, and Democratic Party wins at the presidential level were balanced out by GOP domination of down-ballot races — but that non-Hispanic white majority is shrinking fast.

I've long been skeptical that a majority-minority America would be dominated by Democrats, assuming that both the partisan configuration and the definition of whiteness would shift over time to keep the system in equilibrium. Trump's elevation of racial conflict and identity issues to text rather than subtext of the political debate calls that assumption into question in a manner that really could imperil partisan balance in an unprecedented way.

Donald Trump's ideology of violence