Much has been said about how Donald Trump is the voters’ revenge against a weak and ineffective Republican establishment, but the truth is that he is just as much a rebuke to Democrats, if not more so.

And conservatives who remain worried that The Donald represents an authoritarian style that departs from America’s constitutional tradition ought to consider the importance of the Trump example for the constitutional lessons Republicans, especially the Tea Party, have struggled mightily to teach.

For eight years, conservatives warned about President Barack Obama’s power grabs. These began in small ways that were, at least nominally, constitutional but violated the spirit of co-governance that animates the Constitution’s separation of powers. For example, rather than accept Republican suggestions on the 2009 stimulus bill, Obama simply declared “I won” and went on to push through a near-trillion-dollar failure. Likewise on Obamacare, which he rammed through on a pure party-line vote.

But in 2011, following the Tea Party revolt and the election of a Republican-led House of Representatives, Obama began to violate the Constitution outright. The first example was the Libya war, when he shirked his clear duty to obtain congressional approval, or to report to Congress in the timely manner prescribed by law. (Republicans, perhaps relieved that they would not have to vote on the war, which many quietly supported at the time, did little to point out Obama’s assault on the Constitution.)

In 2012, Obama crossed a dangerous line when he enacted the so-called “Dream Act by fiat,” deferring deportation for several million illegal aliens who happened to have arrived in the U.S. as children. That “executive action” was an obvious attempt to out-flank Republicans, who had stolen a march on the White House with a legislative proposal by Sen. Marco Rubio (R-FL) to address the “Dreamer” problem through Congress. Obama would later expand that deferral to millions more illegal aliens.

After winning re-election, Obama tried “executive action” on a variety of other fronts, from gun control to climate change — all in areas where Congress had clearly declined to allow Obama to do what he wanted, even when Congress had been totally controlled by Democrats. At the time, there were almost no objections from Democrats at all, save for a few law professors — people such as Jonathan Turley of George Washington University, and Larry Tribe of Obama’s own Harvard Law School.

More common were reactions like those of Hollywood director Quentin Tarantino, who applauded Obama’s seizure of power, and urged him to go even further. Tarantino told New York magazine in 2015:

I think [Obama]’s fantastic. He’s my favorite president, hands down, of my lifetime. He’s been awesome this past year. Especially the rapid, one-after-another-after-another-after-another aspect of it. It’s almost like take no prisoners. His he-doesn’t-give-a-sh*t attitude has just been so cool. Everyone always talks about these lame-duck presidents. I’ve never seen anybody end with this kind of ending. All the people who supported him along the way that questioned this or that and the other? All of their questions are being answered now.

Trump’s critics correctly point out that his policies and his rhetoric thus far suggest that he might well reinforce Obama’s unconstitutional expansion of executive power, though he has occasionally said that he would prefer to work with Congress.

But fear of Trump’s overreach is useful in at least one regard. Conservatives warned liberals for years that one day they would regret defending Obama’s power grabs, lest a Republican president follow his example. The prospect of President Trump is driving that point home.

Thankfully, there is no chance Trump will enjoy the same deference from Congress and the media that Obama did. But if liberals finally fear what they themselves have wrought, that lesson is already an achievement.

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. His new e-book, Leadership Secrets of the Kings and Prophets: What the Bible’s Struggles Teach Us About Today, is on sale through Amazon Kindle Direct. Follow him on Twitter at @joelpollak.