If you’re wondering how President Barack Obama’s controversial announcement of a sweeping new set of executive actions designed to shield as many as 5 million illegal immigrants from deportation will reshape U.S. politics in the run-up to 2016, then there’s one place you probably shouldn’t look for answers:

History.

As pretty much every Republican in America has already said, what’s happening right now in Washington is “unprecedented.” But what’s unprecedented about it isn’t Obama’s decision to take unilateral action on immigration. For at least the last 70 years, presidents have routinely “acted first” — before Congress — “to permit the entry of people outside normal channels or to protect large numbers of people from deportation.”

Instead, what’s unprecedented about Washington’s current immigration kerfuffle is the kerfuffle itself: the size, scope and intensity of it. Never before has an opposition party threatened to sue, blackmail or impeach a president for exercising prosecutorial discretion in respect to U.S. immigration law. And never before has a president so plainly aspired to troll his opponents by doing so.

That’s what’s new here: the political noise, the partisan gamesmanship. And because these sorts of battle lines, once drawn, have a way of hardening over time, the consequences of today’s immigration uproar — especially the electoral consequences — may turn out to be unprecedented as well, transforming 2016 into the most ethnically divisive election in recent memory.

To see how different things used to be, turn back the clock 25 years to early 1990, when a Republican president named George H.W. Bush made his own unilateral adjustments to the nation’s immigration system. Eight months earlier, in July 1989, the Senate passed (by an 81-17 vote) a “major overhaul of U.S. immigration,” as the Washington Post put it at the time — a bipartisan bill that would have, among other things, “block[ed] deportation of close family members of aliens legalized under [Ronald Reagan’s] 1986 immigration law.” The measure then stalled in the Democratic House.

That’s when H.W. took matters into his own hands. The following February, with no progress on Capitol Hill, the Bush administration directed the Immigration and Naturalization Service to “liberaliz[e] immigration policy to allow close relatives of legalized aliens to remain in the country while they wait to qualify for permanent residence,” according to a contemporaneous story in the Los Angeles Times.

The administration’s directive expanded the number of family members eligible for relief from deportation, authorized them to obtain work permits and made it clear that the policy should be implemented in “a consistent and humanitarian manner.” Federal Immigration Commissioner Gene McNary said that as many as 1.5 million — a full 40 percent — of America’s 3.5 million illegal immigrants could be shielded by Bush’s order.

Sound familiar? It should. The current Senate also passed a big bipartisan immigration reform bill. The bill also stalled in the House, which is also controlled by the president’s foes. And Obama’s executive action is also designed to defer deportations and provide work authorization to 40 percent of the nation’s illegal immigrants — specifically the ones with strong family ties to the U.S. The only substantive difference is that while “ Bush protected children on behalf of their parents, Obama will protect parents on behalf of their children.”

Which is why it’s so dizzying to learn how the country reacted to Bush’s maneuver back in 1990 — or, rather, didn’t react. An archival search reveals that the INS’s Family Fairness plan was barely mentioned in any of the major U.S. newspapers: an L.A. Times article here, a Miami Herald report there. Maybe 15 pieces total. Bush himself was never mentioned at all; his name doesn’t appear once in the New York Times’ story on the subject. There was no Beltway brouhaha. No congressional food fight. No 24/7 cable news jabberfest about What It All Means. By October 1990, the House and Senate had passed a combined Immigration Act that went further than Bush’s Family Fairness directive on deferred deportation.

Obviously, the situation has changed over the last quarter century. And that’s everyone’s fault. In Bush’s day, House Democrats largely concurred with his Family Fairness plan; today’s House Republicans oppose Obama on everything, immigration included. And Bush didn’t pre-emptively blow up an ongoing immigration debate by circumventing Congress the way Obama did in June 2012. Back then, the president announced that he would unilaterally shield from deportation 1.7 million DREAMers who were brought to America illegally as children — and he did it at the same time Republican Sen. Marco Rubio was trying to kick-start similar legislation on Capitol Hill. Unlike Bush, Obama has counteracted a new pattern of partisan behavior — nonstop congressional obstruction — with a new, partisan pattern of his own. As Daniel Klaidman and I wrote in 2012,

“The result is an extraconstitutional arms race of sorts: a new normal that habitually circumvents the legislative process envisioned by the Framers. On one side of the aisle, Republicans are providing a blueprint for minority parties to come, demonstrating how it is possible, and politically advantageous, to use procedural tricks to incapacitate a president they oppose. On the other side of the aisle, Obama is drafting a playbook for future presidents to deploy in response: How to Get What You Want Even If Congress Won’t Give It to You.”

So how does this new story end? It’s a fool’s errand to make predictions about politics, but in this case there are some tectonic forces at work that will likely keep the narrative from veering off in any radical directions over the next two years. Republicans are bitterly divided over immigration. Some want reform; they tend to hail from states with sizable Latino populations and to recognize that it’s probably not in the party’s long-term interest to keep alienating one of the nation’s fastest-growing demographic groups. Other Republicans oppose reform; they tend to come from deep-red districts where conservative primary challenges are a distinct possibility. Still, there’s one thing both factions agree on: that Obama is a lawless scoundrel for acting unilaterally on immigration.

Now that the president has done just that, it’s doubtful that Republicans will choose to fight among — and possibly imperil — themselves by crafting their own immigration legislation when they can simply band together and battle the president instead: by withholding funds for the Justice Department; by passing a law that counters the president’s order; by running presidential candidates who pledge to overturn it; by suing, blocking, censuring, holding Obama’s nominees hostage and so on.

In short, expect immigration warfare — not reform — for at least the next two years.

Which means that 2016 may be one of our most divisive elections yet. Increasingly, presidential exit polls reflect an electorate split along racial and ethnic lines. Whites are voting more and more Republican. Nonwhites are voting more and more Democratic. In 2008, John McCain won 55 percent of white voters; in 2012, Mitt Romney bumped that number up to 59 percent. Meanwhile, Obama won 67 percent of Latino voters in 2008 — and a historic 71 percent in 2012.

A scorched-earth legislative battle over immigration would only deepen this ethnic divide. As Nate Cohn of the New York Times recently noted, “A close look at demographic data and recent election results suggest that the Republicans do not necessarily need significant gains among Hispanic voters to win the presidency.” All they have to do, at least in the short term, is continue to increase their share of the white vote. Fighting tooth and nail against Obama’s immigration order could be a convenient way to accomplish this goal.

Of course, such a strategy would do even more damage to the GOP’s flagging support among Latino voters — which may be exactly the outcome Obama is angling for. Ultimately, it’s too early to say who will benefit at the ballot box from the president’s unilateral immigration overhaul. But it’s hard to see how our political process will be better for it.