Many conservatives have spent the last year pulling their hair out trying to figure out why so many Republican voters support Donald Trump. They’ve made the case time and again that Trump isn’t actually a conservative or even a Republican.

Other conservatives - many famous - have supported Trump.

Some of these supporters, or at least facilitators, have made millions defending conservatism’s good name. For decades, they’ve participated in ideological battles over who is and who isn’t a true conservative.

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During the 2008 and 2012 elections, they spent a lot of time insisting insurgent libertarian Republican Ron Paul wasn’t a conservative and didn’t belong in the GOP.

I was Ron Paul’s official blogger for his 2012 presidential campaign. A great deal of my writing focused on defending Paul from his attackers on the right.

These conservatives blasted Paul for his unorthodox Republican views, particularly on foreign policy. They denounced Paul for opposing the Iraq war and for attacking the George W. Bush administration.

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The same things Trump says today.

Let’s remember some of the high-profile conservatives who said Paul was a joke, but who embrace Trump.

Ann Coulter: In 2012 - when she was supporting Mitt Romney - Coulter said Paul was one of the least conservative candidates in the race, primarily for his foreign policy stances. Coulter dismissed Paul’s rowdy supporters as being like Justin Bieber fans, but today worries Trump’s fans aren’t violent enough. She even said Paul’s son, Sen. Rand Paul, was too “cranky” to be president in 2016, but Trump might be a gift from God.

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Bill O’Reilly: During the last election, O’Reilly called Ron Paul’s foreign policy “dangerous” and said Paul would not be “nominated by the Republican Party simply because President Obama would beat Mr. Paul by a colossal margin.”

At the time some polls showed Paul could beat Obama. Current polling shows Trump might be the weakest general election candidate since Barry Goldwater.

Rush Limbaugh: Limbaugh said Paul was the most serious fiscal conservative in the race in 2012. Rush has been friendly to his son, Sen. Rand Paul.

But he also said Ron Paul’s “kookiness” would “destroy” the Republican Party if he became the nominee in 2012. Today, Rush says Trump has a much “bigger upside than downside” if he becomes the nominee (again, current polling shows Trump could be one of the worst general election candidate in modern political history).

The rampant hypocrisy among Paul-hating, Trump-loving right-wingers on foreign policy and other issues should be clear. But there’s something more troubling.

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Ron Paul-style libertarianism was harsh on government but always compassionate toward individuals. Trump-style authoritarianism largely embraces big government and collectively blames immigrants, Muslims and others for America’s problems.

What does it say about popular conservative leaders who rejected an anti-establishment libertarian insurgency in Ron Paul, but who embrace a darker, more authoritarian challenge to the status quo in Donald Trump?

What does it say about what these people think conservatism really is?

Jack Hunter, the politics editor for Rare.us, is a special contributor to the Austin American-Statesman.