Sen. Marco Rubio (R-Fla.) at a primary election party, in Kissimmee, Fla., in August. (John Raoux/ASSOCIATED PRESS)

Indignant emails roll out of Marco Rubio’s Senate office in waves, as if the past year hadn’t happened at all.

President Obama is soft on Cuba, they complain. Obama is soft on Iran. Obama should be tougher on Venezuela.

This is Rubio the defender of human rights, Rubio the internationalist, Rubio the brave advocate for U.S. leadership and engagement in a dangerous, dictatorial world.

And Rubio the endorser of Donald Trump? Nowhere to be found in these pronouncements. Unimaginable, in fact, in these pronouncements.

Every down-ballot Republican candidate who has endorsed Trump for president, which is almost every down-ballot Republican candidate, will have to explain the stance to his or her children and grandchildren.

At a debate against Democratic rival Patrick Murphy, Oct. 17, Sen. Marco Rubio (R-Fla.) explained why he believes U.S. elections aren't "rigged," contrary to what GOP presidential nominee Donald Trump says. (WFTV)

None will have more difficulty than strong-U.S. Republicans such as Sens. John McCain of Arizona, Tom Cotton of Arkansas and Rubio of Florida. They have pilloried Obama for weakening the United States’ position in the world. Yet until the sexual-predator video surfaced, they all recommended a vote for someone who would do far greater damage to the United States than Obama ever could — who would destroy the alliances and moral standing they claim to champion. Even after the video, Rubio and Cotton are still on board.

I’ve agreed with many (though by no means all) of these senators’ criticisms of administration policy. Obama’s premature withdrawal from Iraq, Afghanistan and other zones of crisis made the world more dangerous — and forced U.S. troops to redeploy into far less favorable circumstances than they left.

But as evident as Obama’s mistakes have become with time, it is even more obvious that the 2016 candidate most committed to the values these Republicans claim to cherish is Hillary Clinton. She believes in U.S. leadership and engagement on behalf of democratic allies.

Trump, by contrast, trashes the United States’ allies, speaks casually about the use and spread of nuclear weapons and admires the world’s most odious dictators, including Syria’s Bashar al-Assad and Russia’s Vladimir Putin.

What explanation can there be for Rubio’s support of such a man, beyond placing party over country and self-preservation over self-respect?

As he campaigns for reelection, Rubio’s muddy excuses have tended to involve the dangers of electing a Democratic president who would appoint liberal judges to the Supreme Court.

But not so long ago, Rubio understood that even that awesome power is secondary. “I think the most important thing a president will ever do is provide for the national security of our country,” he said a year ago.

“Donald Trump has zero foreign policy experience,” he added as the campaign went on. Trump was a “con artist.” He was “an erratic individual” not to be trusted with the nation’s nuclear codes. He was “a serious threat to the future of our party, and our country.” Trump “praised dictators Saddam Hussein and Moammar Qaddafi, and . . . said China was too soft on dissidents,” Rubio noted. He was “not ready for the test.” His rhetoric “reminds me of third-world strongmen.”

These are not the usual insults traded in the heat of a primary campaign. They represent Rubio’s considered, and accurate, judgment that Trump is unfit to be commander in chief.

“We need to have moral clarity regarding what we stand for and why,” Rubio said in a speech two years ago. “This means reinforcing our alliances. It means resisting efforts by rising and resurgent powers to subjugate their neighbors. It means being unabashed in our support for the spread of economic and political freedom.”

It hardly needs saying that Trump’s positions and inclinations are in direct conflict with every single component of that statement. No one who truly believed those words could also believe Trump belongs in the White House.

Rubio may win reelection. If so, he no doubt will go on churning out fine-sounding statements about moral clarity, alliances and the spread of economic and political freedom. Many of them may be on target.

But every one of those statements will carry an invisible asterisk: “Caution: This is the view of a man who voted for Donald Trump. Believe him at your own risk.”

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