President Donald Trump signs an executive order at the White House (AP File Photo)

It's something most conservatives would not have imagined a year ago: The opening act of Donald Trump's agenda in the White House contains a real whiff of President Ronald Reagan. To be sure, there's plenty the Reaganites won't like — talk of trillion-dollar federal building campaigns, taxing business at the border, etc. — but there's plenty to applaud as well.

He's proposing dramatic across-the-board tax cuts. That's Reaganesque. He's reasserting American strength and resolve in response to the dictators who rattle sabers at America. That's Reaganesque. He appointed a Supreme Court justice who follows the Constitution instead of acting like a superlegislator. That's Reaganesque. He's working diligently to reduce the power of Washington, D.C. That's mega Gipper.

What's missing? Craig Shirley has emerged as perhaps the most knowledgeable historian of Reagan alive today. His fourth biography is out, and it's every bit as fascinating as the first three. "Reagan Rising" connects the dots between the 1976 and 1980 campaigns. President Trump and/or his closest advisors need to read this book.

Shirley drives home a key point: Reagan did not run against the Democrats. He did not run against the left. He ran against the establishment — at the time dominated by liberal Democrats but not limited to them. If he was to become president, he also had to defeat the Republican establishment of moderates, whose collective blood curdled at the thought of him being elected.

Shirley writes that on Jimmy Carter's Inauguration Day in 1977, outgoing President Gerald Ford told a reporter as he flew out of town that he would like to run again in 1980. He added, "I don't want anyone to preempt the Republican presidential nomination." He meant Reagan.

The establishment narrative was repeated constantly: Reagan was racist, sexist, homophobic, imperialist, an evil manipulator, dumb as a board and completely over his head.

Reagan championed American exceptionalism. He didn't wish greatness for America. It already was great. He called for a return to it. America could become the strongest economic force in America — again. America could become the leader of the free world — again. America could become a civil society — again. In advancing these themes, he was directly challenging and threatening the GOP establishment. It was content with bloated federal power, high taxes, live-and-let-live detente and (foremost) the societal decomposition of abortion.

Trump is facing the same establishment hostility because he poses the same threat (maybe an even larger one) to its power. But there's a huge difference: his response. The issue is one of temperament, which Shirley captures so well because he understands Reagan so well.

Trump and Reagan had the same slogan, except for one all-important thing missing from Trump's version. In "Let's Make America Great Again," Reagan was inviting America to join him as his partner in this crusade. As Shirley reminds us, in Reagan's acceptance speech at the 1980 Republican convention in Detroit, he said "we," "us" and "our" more than 200 times. Compare that to these painful last eight years, when President Obama used "I" or "my" hundreds of times in his speeches.

Candidate Trump — the Donald — has always tilted toward Obama's boastfulness. President Trump needs to stop that. Reagan's humility and confidence inspired the country. Trump must do the same if he wants to succeed. He has the refreshing confidence. He needs to find his inner public humility.

No one can tell Donald Trump that he doesn't know how to win in politics. Governance, as he's learning, is another animal. Trump sees himself as transformational, and that is good. He will not be content with just dismantling the disasters created by Obama. He will push — and is already pushing — a boldness we haven't seen in GOP presidents, or even most GOP candidates, since Reagan.

Maybe he should invite Craig Shirley to the Oval Office for a long chat.

L. Brent Bozell III is the president of the Media Research Center. Tim Graham is director of media analysis at the Media Research Center and executive editor of the blog NewsBusters.org.