One of California’s largest counties has thrown its support behind President Donald Trump Donald John TrumpBubba Wallace to be driver of Michael Jordan, Denny Hamlin NASCAR team Graham: GOP will confirm Trump's Supreme Court nominee before the election Southwest Airlines, unions call for six-month extension of government aid MORE’s effort to halt the dangerous Sanctuary State law.

Now, Trump has thrown his support behind them.

ADVERTISEMENT last night that his administration “stands in solidarity” with “the brave citizens” of Orange County, Trump acknowledged the county’s bold 4-0 action to direct their legal counsel to join the United States’ lawsuit against the rogue state.

The fact that California’s third-most populous county — weighing in at a whopping 3 million citizens — chose to stand up to Gov. Jerry Brown (D) is significant. It has not only taken a page from “The Resistance” and flipped that narrative back onto the democratic leadership in that state, but its historic role in fights signals that the sanctuary state showdown is about to get even more interesting.

With its massive prowess, Orange County’s resistance could serve as the lynchpin for the beginning of the end of California’s ill-advised law.

For starters, it is the largest county to date to sign on to the administration’s lawsuit against the state, which will undoubtedly carry weight as the case to strike down the dangerous sanctuary law moves through court this spring. The sheer population of the county creates an interesting tsunami of opposition to Gov. Brown. The county’s vote makes the action taken earlier this month by the small town of Los Alamitos, albeit brave, look like a day at the kiddie pool.

It is also worth mentioning that when the leaders of Orange County get behind something, they usually succeed — “bigly.”

Orange County was the birthplace of the historic California Recall, which toppled sitting democratic Gov. Gray Davis (D) over his mismanagement of the state and elected Governor Arnold Schwarzenegger (R). I’m not suggesting there could be grounds for a recall of Brown over the Sanctuary State law (although the idea is intriguing), but the recall is instructive of the power that Orange County yields.

The conservative county was also the birthplace of Citizens United — the landmark case banning limits on campaign contributions that went all the way to the United States Supreme Court. Citizens United vs. Federal Election Commission paved the way for unlimited money via Super PACs and anonymous donations by corporations, and it has driven liberals to near convulsions.

Orange County is also the birthplace of Prop. 8 — the landmark ballot initiative to uphold traditional marriage that sparked the national conversation on religious liberty and marriage equality which, not unlike Orange County’s Citizens United, also went all the way to the Supreme Court.

Orange County was even the literal birthplace of Prop. 8’s conservative funders who also supported its predecessor, Prop. 22, which succeeded for conservatives fighting for traditional marriage nearly a decade prior.

In fact, with so many political successes Orange County has been called "the ideological birthing place for California Republicanism” dating all the way back to President Richard Nixon — who also happened to be birthed in Orange County. Friends of Nixon set up camp at a compound in Orange County which his supporters at the time nicknamed “the Western White House.” The National Register of Historic Places has since deemed it so. It was here that numerous republican ideas were hatched.

It was in Nixon’s California heyday that Walter Knott, founder of Knott’s Berry Farm, and Si Flour, founder of the Fluor Corporation, founded the all-powerful Lincoln Club of Orange County — a group that birthed the two of the above movements, plus a few more.

In addition to the above California Recall and Citizens United, the Orange County power brokers also launched the landmark Prop. 13 — which limited in how much the government could tax property when California housing prices boomed and more importantly, demanded that any tax increase must be passed by a two-thirds majority in the legislature.

The 1978 initiative was a major thorn in the side for a young governor at the time named, yep, you guessed it — Jerry Brown. It remains a thorn in the side of California democrats today, who seek to repeal it to this day.

Last but certainly not least, Gov. Pete Wilson’s (R) Prop. 187 (also known as the “Save Our State” initiative) in 1994 was also born in none other than Orange County. It was a successful ballot initiative to establish a state-run citizenship screening system and prohibit illegal immigrants from using non-emergency health care, public education, and other services in the state of California.

The ballot initiative introduction read, “The People of California find and declare as follows: That they have suffered and are suffering economic hardship caused by the presence of illegal immigrants in this state. That they have suffered and are suffering personal injury and damage caused by the criminal conduct of illegal immigrants in this state. That they have a right to the protection of their government from any person or persons entering this country unlawfully.”

Although the measure’s messaging was ultimately hijacked by the left and turned against the GOP, its message was prescient. In the wake of Kate Steinle’s murder and today’s illegal immigration debate in the golden state, Wilson stands by it. He said last year not only would he support the measure all over again but with his tough stances he left the state “a hell of a lot better” after eight years in office.

One can clearly see that in nearly every battle for California’s future and the future of the national conservative movement, the road to victory passed directly through Orange County. Without the conservative bastion, California democrats would have run roughshod over its population long ago.

The message is clear: don’t mess with Orange County.

The power of Trump’s presidential bully pulpit, combined with Orange County’s track record of political success, spells certain trouble for democrats. With these two forces joining efforts, there is no telling what the next development could be in the fight for the future of California and the fate of the rest of the nation.

In this sanctuary state showdown, the country and the conservative movement find itself once again depending upon Orange County. Just as in previous fights, I know firsthand that it won’t disappoint.

Jen Kerns has served as a GOP strategist and writer for the U.S. presidential debates for FOX News. She previously served as communications director and spokeswoman for the California Republican Party, the Colorado Recalls over gun control, and the Prop. 8 battle over marriage which went all the way to the U.S. Supreme Court.