WASHINGTON — When Donald Trump made his entrance to the packed Verizon Center on Monday night, the applause from the 18,000 AIPAC conference participants was polite, even warm, but certainly not overwhelming. There was a half roar from the higher reaches of the stadium, and a few isolated cheers.

Unlike the previous speaker, Paul Ryan, Trump did not bound onto the stage. He approached the microphone slowly, even hesitantly. Was the indomitable Republican front-runner perhaps a little nervous about addressing what CNN had described as arguably his most challenging audience?

As it quickly turned out, not a bit.

Trump delivered a river of emphatically pro-Israel sound bites to a crowd that applauded with increasing enthusiasm as he progressed. Soon he was having to pause for brief standing ovations. Then he was giving the thumbs-up signal. Now he was waiting, lips pursed, shoulders shrugging, palms out, as if to say: You know I’m right, and I’m the only one with the guts to say it.

US Republican presidential hopeful Donald Trump waves at the American Israel Public Affairs Committee (AIPAC) 2016 Policy Conference at the Verizon Center in Washington, DC, March 21, 2016. / AFP / SAUL LOEB

US Republican presidential hopeful Donald Trump waves at the American Israel Public Affairs Committee (AIPAC) 2016 Policy Conference at the Verizon Center in Washington, DC, March 21, 2016. / AFP / SAUL LOEB

By the mid-point, he was able to castigate Hillary Clinton as “a total disaster, by the way” — hours after she had delivered a carefully crafted, thoroughly pro-Israel and well-received address here — and garner what sounded like as much applause as howls of disapproval. And by the end, many were cheering him — emphatically not all, but many — sorry it was all over so soon.

AIPAC’s Policy Conference a tough audience for Donald J. Trump? It was easy, even for a candidate lambasted by the Anti-Defamation League just days ago for slandering minorities and bringing intolerance into the American political mainstream, a candidate who has difficulty disavowing the support of white supremacists.

Troublingly for the pro-Israel lobby, whose bipartisan credentials are central to its credibility and effectiveness, he also had substantial sections of the audience applauding when he described President Barack Obama as arguably “the worst thing that ever happened to Israel.”

Clearly, Donald Trump is a highly effective speaker. The revelation was that this audience, whom AIPAC had worried might protest the candidate too rudely, was so efficiently, almost effortlessly won over. Some had walked out in protest at his appearance; they were a very small minority.

Some of what the candidate said was implausible. He asserted that it had been “very dangerous” for him to have taken the role of grand marshal of New York’s Israel Day Parade in 2004. “I took the risk and I’m glad I did.” And some of what he said was ridiculous. While scorning the Iran deal, he declared that, “I’ve studied this issue in great detail” — indeed, “I would say greater by far than anybody else.” Large sections of the crowd laughed out loud at the absurdity of the boast, but Trump gave no sign of having been joking. “Believe me, oh, believe me,” he assured them.

Yet he won steadily growing applause because of the sheer unceasing flow of unabashedly pro-Israel rhetoric, before an audience more acutely conscious than almost any other of the rarity of such no-holds-barred support. His first two sentences were: “I speak to you today as a lifelong supporter and true friend of Israel. I’m a newcomer to politics but not to backing the Jewish state.” The empathy for Israel and outrage at its treatment — by the Obama Administration, the UN, the Arab world — only grew in intensity from there.

Democratic presidential candidate Sen. Bernie Sanders, I-Vermont, waves after speaking at a campaign rally at the Akron Civic Theatre in Akron, Ohio, Monday, March 14, 2016. (AP Photo/Tony Dejak)

Democratic presidential candidate Sen. Bernie Sanders, I-Vermont, waves after speaking at a campaign rally at the Akron Civic Theatre in Akron, Ohio, Monday, March 14, 2016. (AP Photo/Tony Dejak)

Meanwhile, even as Trump was speaking, news reports were coming in of an undelivered speech released by the one presidential candidate who had skipped the AIPAC policy conference, the one Jew in the race, Bernie Sanders. Off campaigning in Salt Lake City, Sanders made public a speech he had understandably chosen not to make at AIPAC, in which he lambasted Israel for its ostensible “disproportionate responses to being attacked,” criticized its “bombing of hospitals, schools and refugee camps” in the 2014 war with Hamas, and demanded an end to Israel’s “blockade of Gaza” (with no acknowledgment of why the blockade is maintained, to prevent the importation of weapons by a terror group declaredly intent on wiping Israel out).

Here in DC, by utter contrast, Trump was promising that his “number one priority” as president would be to dismantle “the disastrous deal with Iran.” And no matter that, minutes later, he was merely pledging to “enforce its terms.”

Here in DC, Trump was vowing, “when I’m president,” to “totally dismantle Iran’s global terror network.” He was expressing his horror at “the demented (Iranian) minds” that would write a pledge to destroy Israel on their UN-defying tests of ballistic missiles. He was deriding “the utter weakness and incompetence of the United Nations.” He was committing to resist any attempt to impose peace terms on Israel. He was swearing to “confront” Palestinian terrorism, to “move the American embassy to the eternal capital of the Jewish people, Jerusalem,” to “send a clear signal that there is no daylight between America and our most reliable ally, the state of Israel.” And in perhaps his most applauded line, he was declaring that “When I become president, the days of treating Israel like a second class citizen will end. On day one.”

Trump was pushing all the right buttons, offering unstinting praise for Israel to a pro-Israel constituency starved of uncritical support for a lot longer than two terms of government. And the response, in parts of the stadium at least, gradually moved toward adulatory.

US Republican presidential hopeful Donald Trump gives a thumbs-up as he arrives to speak during the American Israel Public Affairs Committee (AIPAC) 2016 Policy Conference at the Verizon Center in Washington, DC, March 21, 2016. / AFP / SAUL LOEB

US Republican presidential hopeful Donald Trump gives a thumbs-up as he arrives to speak during the American Israel Public Affairs Committee (AIPAC) 2016 Policy Conference at the Verizon Center in Washington, DC, March 21, 2016. / AFP / SAUL LOEB

By the time he staged his most audacious gambit, his most divisive gambit, much of the crowd was in the palm of his outstretched hand. “With President Obama in his final year, YAY,” he began. And then he paused for the roar of approval he knew would come. And come it did — to the doubtless extreme discomfort of the AIPAC leadership. Trump stood and waited and smiled and shook his head a little. And then he followed up with, “He may be the worst thing that ever happened to Israel, believe me, believe me.” And the applause welled up again. Not wall-to-wall, but plenty of it. “And you know it. And you know it better than anybody.”

Obama and Clinton have “treated Israel very badly,” he said. Many in this audience plainly agreed with him.

Inside the Verizon, there was no talk of “neutrality” on the Israeli-Palestinian issue. There was no repeat of his comment, just hours earlier, that Israel should pay for its US defense aid. Instead, Trump was now moving toward his conclusion. “I love the people in this room. I love Israel… My daughter Ivanka is about to have a beautiful Jewish baby.” (Massive roar of applause.) “In fact it could be happening right now, which would be very nice as far as I’m concerned. So I want to thank you very much. This has been a truly great honor. Thank you everybody.”

And with that, the stream of staccato sentences halted. He waved. He beamed. He held the thumb aloft again. And he was gone. Gone in 25 minutes.

Over the two preceding days of the AIPAC conference, various delegates had described Trump to me in private conversations as a demagogue, as a man unleashing dark political forces in America, even as an “accidental Mussolini.” When you look at the video of his Monday night performance, you’ll see that AIPAC’s fears that he would be rudely treated here, that he would be booed and jeered and made to feel unwelcome, proved entirely unjustified.

What should we all make of that?