President Donald Trump, left, and Russian President Vladimir Putin arrive for a press conference after their meeting at the Presidential Palace in Helsinki, Finland, July 16, 2018. Credit: Alexander Zemlianichenko | AP

It has been 30 years since Princeton University professor James McPherson published his extraordinary “Battle Cry of Freedom: The Civil War Era,” which won a much deserved Pulitzer in 1989. Great books remain references for decades, and now the book deserves a rebirth of sorts. Listening to McPherson’s account of the 1850s, for example, is oddly relevant even as history makes clear that the relatively young Union was in a far more perilous condition then than ours is today.

There is no “Bleeding Kansas,” for example, but there are some powerful reminders that political DNA moves down the generations as surely as human genes do. The Republican Party was birthed in the 1850s, and most people know that Abraham Lincoln was its second nominee for president and its first successful one. The party that nominated him in 1860 was the product of a deft absorption of members from another party: the Know-Nothing party.

The Know-Nothings were a party built on opposition: “anti-liquor, anti-Catholic, and anti-immigrant,” though Northern and Southern party members were split on the question of slavery. Primarily “young men in white-collar and skilled blue-collar occupations,” they organized themselves into hundreds of “lodges” across the country in the 1850s in the wake of mass waves of immigration. “Members were pledged to vote for no one except native-born Protestants for public office,” McPherson recounts. “When asked by outsiders about the Order, members were to respond ‘I know nothing.’”

The Republicans were primarily a new party of liberty and opposition to “the slave power,” but before they could approach power, they needed to co-opt northern Know-Nothings. This they did by various moves — deft and often disingenuous nods and winks. “Of their principles,” Lincoln wrote in 1855, “I think little better than I do of the slavery extensionists,” yet they “are mostly my old political and personal friends.”

These nativists were absorbed into the much broader struggle against the South. Their party disappeared. Their political DNA, never a majority but never insignificant, passed on through 16 decades of GOP evolution. The movement collapsed into the convulsion of the era, but a platform of grievances of those who perceived themselves to have built the country against those new to the country did not die off, and it never will for any nation open to immigrants. There will always be this tension between the new and striving and the old who have investment and labor already sunk into the land.

President Donald Trump took over the GOP riding the old Know-Nothing movement’s modern counterpart — evolved to no longer be anti-Catholic or pro-temperance, but very much a reflection of rapid change and disintermediation, the fears and shocks of terrorism and economic panic of the new millennium combined with 24/7 media. Where the first Republicans beat the Know-Nothings in the 1850s, the GOP establishment was helpless to stop Trump’s extraordinary hostile takeover of the party.

But the party doesn’t change just because it’s captained for a time by an outsider channeling the grievances — some real, some imagined — of millions of stakeholders seeing what they built dissolve into uncertainty. Hardly 1 in 10 elected Republicans cheers all of the president’s agenda, but close to 90 percent are willing to hang on for the ride, at least a while.

Trump delivers traditional Republicans the military buildup, deregulation, tax cuts and, crucially, judicial appointments of the sort that would make the Eisenhower, Nixon, Reagan and both Bush coalitions happy. But the party has internal “red lines,” and one of them is national strength and national security in service of the rule of law. It is not isolationist, and it will shatter before abandoning liberty-loving allies for dictators.

When Trump fell into the “Nixon trap” of believing himself able to change geopolitics with a single flip of the foreign policy script in Helsinki (just as Barack Obama indulged the same vanity vis-a-vis Iran), the party’s long-dominant internationalist-realist majority recoiled. Dealing with Vladimir Putin is fine depending on the terms. Pretending he is anything other than a dictator who has repeatedly attacked not just our elections but also U.S. allies and interests across the globe is not.

The nativist pulse of the 1850s was not a majoritarian movement. It was a junior partner in the coalition that powered the Republican Party to save the Union and the Constitution. That the pulse returned and captured the presidency does not change the party of freedom’s true north. That lodestar is protecting the Constitution and equality of opportunity for all Americans regardless of race, gender, religion, ethnicity and sexual orientation, and doing so with military strength and clarity about who are our friends and foes around the globe.

Hugh Hewitt hosts a nationally syndicated radio show and is author of “The Fourth Way: The Conservative Playbook for a Lasting GOP Majority.”

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