An old proverb sums up how Donald Trump handled the last two days: “The dogs bark but the caravan moves on.”

The dogs of the Democratic media were absolutely howling yesterday over sordid, unverified allegations involving Russia, but the president-elect and his team put on a master class in self-defense. They hit back forcefully, with press secretary Sean Spicer calling publication of the allegations “disgraceful” and Vice President-elect Mike Pence calling it a case of “fake news” that aims to “delegitimize the president-elect.”

It was a strong warm-up, and Trump then took the stage to completely deny the charges, and repeated the denials in response to numerous questions. By the end of the press conference, he had managed to turn the spotlight away from himself and on to the lack of integrity in both the media and government intelligence agencies — where it also belongs.

That was no mean feat, and his performance was a reminder that Trump is not and never will be a pushover. He fights fire with fire and is getting increasingly more disciplined in making his case.

Pulling it off was not as easy as he made it look. The run-up to his first press conference since winning the election had the air of crisis that was routine in the long campaign. Then, every week or two, many geniuses predicted that something Trump had said or done would be the final straw and he would have to drop out.

Similarly, the salacious allegations he faced yesterday packed a potential to seriously wound him before he takes office. Anything less than complete denial would have created a firestorm, but after his no-wiggle-room statements, the allegations withered, at least for now. That had to disappoint the dead-enders who hoped they had finally found the kill shot.

Instead, Trump emerged intact and even stronger as he made news on two other fronts: He released extensive plans on how he is severing himself from his company and nominated a new secretary of the troubled Department of Veterans’ Affairs.

With his first Cabinet nominees getting good reviews in confirmation hearings, Trump is clearing a final series of hurdles before taking the oath. There is a sense of optimism about the economy, and his announcements on various job deals are making his transition far more meaningful than most.

Yet the opposition to him, especially in Washington, remains formidable, with the latest allegations an example of how low some people are willing to go. For one thing, numerous reports say the anonymous charges were the product of opposition research paid for by Trump’s Republican opponents, with the payments then continued by Hillary Clinton supporters.

Indeed, Clinton and associates several times suggested during the race that bombshells involving Trump and Russia were coming, and her campaign chairman is publicly fuming now that the allegations did not surface before the election. It is not fanciful to wonder if Clinton operatives gave them to reporters.

For another thing, the incident showed that a very thin line separates mainstream media from less reputable outlets. BuzzFeed, a liberal Web site, published the 35 pages of memos Tuesday evening that accuse Trump of numerous misdeeds even as its editor said, “there is serious reason to doubt the allegations.”

Nonetheless, in an instant, The New York Times, The Washington Post and others released stories describing the content of the memos without actually publishing them. Those and other large organizations said they had received the memos months ago and had withheld making them public because they could not verify the allegations. Yet because BuzzFeed went ahead, the others felt obliged to do their own stories lest they be scooped.

Once upon a time, it was a good thing to be scooped on a bad story. And ask yourself this: Would the Times and Washington Post make the same decision if the unverified allegations were about PresidentBarack Obama or Hillary Clinton? Of course not, so their rabid anti-Trump agenda still distorts their decision-making.

Which brings us to the most troubling aspect of all — the role of the CIA, FBI and other intelligence agencies in the sordid affair. Trump has been feuding with them for months and plans a shakeup of the sprawling intelligence apparatus.

In that context, Sen. Chuck Schumer recently warned him, “You take on the intelligence agencies — they have six ways from Sunday at getting back at you.”

Is that what just happened here? Was the next president the target of our own spooks?

It is a sign of our troubled times and of Trump’s unprecedented impact even to ask the questions. But it is no secret that most if not all the intelligence leaders wanted to see Clinton in the White House, if only because she is the devil they know. That’s a plausible explanation, but not an excuse.

For now, all we know is that a madness has been set loose in America and there is no reason to believe we have seen the last attempt to destroy Donald Trump.