In a speech before one of the country's largest pro-Israel lobbying groups, Trump proclaimed that, "the days of treating Israel like a second-class citizen will end on day one" of his presidency.
He told the American Israel Public Affairs Committee that "there is no moral equivalency" between Israel and the Palestinians, and he slammed Palestinians for fostering a society that glorifies terrorists as "heroes" and "martyrs."
The billionaire businessman's speech Monday was notable not just for its content but for its delivery, as Trump read from prepared remarks -- seemingly from two teleprompters standing to his right and left. In the past, Trump has slammed politicians for using teleprompters.
Trump's address Monday was also the first of his campaign in which he read entirely from a prepared text -- save for a few off-the-cuff additions like noting that his daughter Ivanka is about to give birth to a Jewish baby. That marked departure comes as Trump seeks to unify the Republican Party around his candidacy and he looks to prove he can be presidential.
Trump had previously said he would be "a neutral guy" in seeking a peace settlement in the decades-old conflict, drawing the ire of pro-Israel supporters in both parties.
And as GOP rival Sen. Ted Cruz was quick to point out as he took the stage after Trump, the Republican front-runner's attempts to appeal to the pro-Israel crowd hit an awkward snag when he repeatedly referred to the Palestinian Authority as "Palestine."
"Perhaps to the surprise of the previous speaker, Palestine has not existed since 1948," Cruz said to some 18,000 pro-Israel advocates.
Earlier on Monday, in an interview with CNN's Wolf Blitzer, Trump said he would still like to be "neutral" in the conflict but said that "it's probably not possible."
Trump also reiterated in his CNN interview that he would pursue a peace deal, calling it "the all-time Olympics to make that deal between the Israelis and the Palestinians."
While Trump pledged from the outset that he had not come to "pander" to the pro-Israel crowd, the unequivocally pro-Israel stances Trump laid out Monday marked a departure from several of his previous statements concerning Israel and the Palestinians.
Despite pledges from Jewish leaders to protest or walk out on Trump's speech, there were no visible disruptions as the Republican delivered his speech.
And Trump earned the audience's favor as his speech went on, receiving more enthusiastic applause from the audience as he delivered one crowd-pleasing line after the next.
Trump also appeared to change his position on the Iran nuclear deal, declaring at the top of his speech that his "No. 1 priority is to dismantle the dismantle the disastrous deal with Iran."
But moments later, Trump said he would "enforce it like you've never seen it enforced before," comments more in line with the stance he has laid out over months of campaigning.
The Trump campaign did not return multiple requests for comment seeking clarification on Trump's position.
Trump also launched into a markedly sharper condemnation of Palestinian society Monday than he has in the past, arguing it fosters terrorism.
"You have rampant incitement and children being taught to hate Israel and hate the Jews," Trump said. "When you live in a society where athletes and movie stars are heroes, little kids want to be athletes and movie stars. In Palestinian society, the heroes are those who murder Jews -- we can't let this continue, we can't let this happen any longer."
Trump also pledged to move the U.S. Embassy in Tel Aviv to Jerusalem, a common GOP refrain though both Democratic and Republican presidents have declined to do so, waiting until the status of the disputed city is resolved in a peace settlement.
Trump said earlier Monday that it his new team of foreign policy advisers hadn't helped him craft his speech to AIPAC but his Jewish son-in-law, who Trump said consulted with friends of his in Israel.
But Trump's new tune on the Israeli-Palestinian conflict did not keep his opponents from slamming his position, as Cruz did in his address to the conference moments after Trump departed the stage.
"As president, I will not be neutral. America will stand unapologetically with the nation of Israel," Cruz said Monday to raucous applause.
Ohio Gov. John Kasich preceded Trump on Monday night and outlined traditional Republican views on Israel, slamming Palestinian terrorist violence against Israeli civilians and reiterating his commitment to holding Iran accountable for its actions.
Kasich vowed to "strengthen and expand" the U.S.-Israel relationship and called recent Iranian missile tests violations of the new nuclear deal.
"We must put the sanctions back on them as the world community together," argued Kasich, who is currently third in the delegate race for the Republican nomination.
Kasich also pinned blame on Palestinian society for the violence of terrorists, arguing, "Palestinians cannot continue to promote a culture of hatred and death."
Kasich also addressed the ISIS threat, which he called "a threat to all civilization."
"Unless we recognize and unite around this central truth, we will remain committed to an ineffective, and piecemeal approach to dealing with ISIS," Kasich said.
Democrat Hillary Clinton
on Monday was the first presidential candidate to address AIPAC, and used her address to attack Trump on his previous statements that he would be "neutral" in the Israeli-Palestinian conflict.
Without naming him, Clinton repeatedly knocked Trump for his position on Israel and other issues.
"We need steady hands, not a president who says he's neutral on Monday, pro-Israel on Tuesday and who knows on Wednesday," Clinton said to applause. "Israel's security is non-negotiable."
She continued, "We can't be neutral when rockets rain down on residential neighborhoods, when civilians are stabbed in the street, when suicide bombers target the innocent. Some things aren't negotiable, and anyone who doesn't understand that has no business being our president."
Clinton also criticized the Republican front-runner and her potential opponent in the 2016 general election for his calls to temporarily ban all foreign Muslims from entering the U.S. and "playing coy with white supremacists" -- a reference to Trump's failure to immediately condemn the support he's received from white supremacist groups.
"We've had dark chapters in our history before," Clinton said before pointing to America's refusal to allow a ship packed with Jewish refugees to dock in the U.S. in 1939.
"But America should be better than this, and I believe it's our responsibility as citizens to say so. If you see bigotry, oppose it. If you see violence, condemn it. If you see a bully, stand up to him," Clinton said.
While a group of rabbis and other pro-Israel leaders are planning to protest Trump's speech later Monday at AIPAC, Clinton's speech Monday was well-received as the audience of Israel supporters loudly cheered throughout her address -- and not just when she reamed Trump.
Clinton also laid out the shared challenges that the U.S. and Israel face in the Middle East and pledged to take the relationship between the two countries "to the next level" if elected president.
"While the turmoil in the Middle East presents enormous challenge and complexity, walking away is not an option," Clinton told the conference, adding that those threats make "the U.S.-Israel alliance more indispensable than ever."
The former secretary of state and senator from New York pointed to her longstanding commitment to a strong U.S.-Israel relationship and took the opportunity to condemn the spate of terrorist attacks that have plagued Israel in the last year, calling on Palestinian leaders to "stop inciting" violence and rewarding the families of terrorists.
Though she has deep ties to Israel and the Jewish community, she has also been part of an Obama administration often at odds with that of Prime Minister Benjamin Netanyahu. Some in the pro-Israel community have knocked her for her part in several years of frosty relations as the country's chief diplomat.
Clinton, however, suggested on Monday that she would take a different course were she elected to replace President Barack Obama. She said soon into her time in the Oval Office she would look forward to receiving the Israeli Prime Minister there.
Clinton also vowed to maintain Israel's qualitative military edge in the region and also spoke to her longstanding commitment to Israel, noting that she feels a "deep emotional connection with Israel" stemming from her first visit to the Jewish nation 35 years ago.
Clinton, whose role in laying the groundwork for the Iran nuclear deal during her time in President Barack Obama's administration may be a sore point for some pro-Israel leaders, also addressed her plans to enforce the agreement.
"It's not good enough to trust and verify. Our approach must be distrust and verify," Clinton said, repeating a line she used last year in a speech at the Brookings Institution aimed at reassuring pro-Israel supporters of her commitment to protecting Israel's security.
Calling on Palestinian leaders to stop fostering and instead condemn terrorism, Clinton also said "everyone has to do their part by avoiding damaging actions," which Clinton said included Israel's continued settlement construction in the West Bank.