Israeli Prime Minister Benjamin Netanyahu defended Israel’s war in Gaza and condemned American protesters in a scathing speech to Congress on Wednesday that was boycotted by many top Democratic lawmakers and drew thousands to the Capitol to condemn the war and the humanitarian crisis it has created.

Netanyahu vowed to press on with the war until “total victory,” disappointing hopes by some that the Israeli leader’s visit to the United States could bring some breakthrough in negotiations for a cease-fire and hostage release.

Speaking to applause from many U.S. lawmakers, and stony silence from others, Netanyahu sought to bolster U.S. support for his country’s fight against Hamas and other Iran-backed armed groups.

“America and Israel must stand together. When we stand together something really simple happens: We win, they lose,” said Netanyahu, who wore a yellow pin expressing solidarity with the Israeli hostages held by Hamas.

But the Israeli leader soon pivoted to a darker tone as he derided those protesting the war on college campuses and elsewhere in the U.S., gesturing to demonstrations happening on the streets outside the Capitol. He called protesters “useful idiots” for Israel’s adversaries.

The line drew shouts of applause from many gathered for the joint session of Congress, but silence from leading Democrats who declined to stand and cheer.

Freed former hostages of Hamas and families of hostages listened in the House chamber. Lawmakers of both parties rose to applaud the Israeli leader in some moments in the speech. Security escorted out protesters in the gallery who rose to display T-shirts with slogans demanding that leaders close a deal ending the conflict and freeing hostages.

Netanyahu accused the protesters in the United States of standing with the militants who, he noted, killed babies in Hamas’ attack on Oct. 7. “These protesters that stand with them, they should be ashamed of themselves,” he said.

Netanyahu — who is frequently accused of wading into U.S. politics in favor of conservative and Republican causes, and who was speaking at the invitation of GOP lawmakers, not the White House — started his remarks with praise of President Biden. He also turned to lavishing praise on former president and Republican presidential nominee Donald Trump “for all he’s done for Israel.”

With criticism against him rising in Israel, Netanyahu aimed to portray himself as a statesman respected by Israel’s most important ally. That task is complicated by Americans’ increasingly divided views on Israel and the war, which has emerged as a key issue in the U.S. presidential election.

Tall steel barriers ringed the Capitol on Wednesday, and police deployed pepper spray as thousands of protesters rallied near the Capitol, denouncing Netanyahu as a “war criminal” and calling for a cease-fire.

Netanyahu received a warm welcome from House Speaker Mike Johnson of Louisiana and other Republican lawmakers who arranged his speech. Netanyahu received a bipartisan standing ovation before speaking.

The appearance made Netanyahu the first foreign leader to address a joint meeting of Congress four times, surpassing Winston Churchill.

More than 50 Democrats and political independent Bernie Sanders boycotted Netanyahu’s speech. The most notable absence was right behind him: Vice President Kamala Harris, who serves as president of the Senate, said a long-scheduled trip kept her from attending.

The next Democrat in line, Sen. Patty Murray of Washington, declined to attend, so Sen. Benjamin L. Cardin of Maryland, the chair of the Senate Foreign Relations Committee, served as Senate president pro tempore in place of her.

Rep. Rashida Tlaib, a Michigan Democrat who has family in the West Bank, sat in the House chamber with a kaffiyeh, which she often wears, wrapped over her shoulders. At times during Netanyahu’s speech, she held up a sign that said “war criminal.”

Tlaib was censured last year for her criticism of Israel’s conduct in the war.

Republicans said the absence of Harris, the new Democratic front-runner for the presidency, was a sign of disloyalty to an ally. Former President Trump’s running mate, J.D. Vance, was also a no-show for Netanyahu’s speech, citing the need to campaign.

Netanyahu is scheduled to meet with President Biden and Harris on Thursday, and with Trump at Mar-a-Lago on Friday.

Many in the swelling crowds of demonstrators protested the killings of Palestinian civilians in the war, a large proportion of the more than 39,000 killed in Gaza. Others condemned Netanyahu’s inability to free Israeli and American hostages taken by Hamas and other militants during the Oct. 7 attack that sparked the war.

Support for Israel has long carried political weight in U.S. politics. But the usual warm welcome for Netanyahu’s visits has been diminished this time around by political turmoil, including the assassination attempt against Trump and Biden’s decision over the weekend not to seek another term.

Many Democrats who support Israel but have been critical of Netanyahu saw the address as a Republican effort to cast itself as the party most loyal.

Many Democrats attended the address despite their criticism of Netanyahu, including Senate Majority Leader Charles E. Schumer, who called for new elections in Israel in a March floor speech. Schumer, of New York, said then that Netanyahu has “lost his way” and is an obstacle to peace in the region amid the humanitarian crisis in the Gaza Strip.

About 60 lawmakers met Wednesday with relatives of those taken hostage by Hamas, and they expressed anger toward Netanyahu. “Because by coming here, he risks making himself the issue, turning the humanitarian issue of the hostages into a political one,” Maya Roman, who had several family members taken hostage, told the lawmakers.

The United States is Israel’s most important ally, arms supplier and source of military aid. Netanyahu’s visit is his first abroad since the war started, and comes under the shadow of arrest warrants sought against him by International Criminal Court prosecutors over alleged Israeli war crimes against Palestinians. ICC prosecutors are also seeking warrants against Hamas leaders accused of war crimes. The United States does not recognize the ICC.

The Biden administration says it wants to see Netanyahu focus his visit on helping to complete a deal for a cease-fire and hostage release. Growing numbers of Israelis accuse Netanyahu of prolonging the war in order to avoid a likely fall from power whenever the conflict ends and elections are held.

Netanyahu has said his aims for the U.S. visit are to press for freeing hostages held by Hamas and other militants in Gaza, to build support for continuing Israel’s battle against the group, and to argue for continuing to confront Hezbollah in Lebanon and other Iranian-allied groups in the region.

Some Democrats are wary about Netanyahu since he used a 2015 joint address to Congress to denounce then-President Obama’s pending nuclear deal with Iran. Then, as now, he circumvented the White House and spoke to Congress at the invitation of Republican lawmakers.

Netanyahu used an appearance early Wednesday to focus on Iran, its nuclear program and its network of armed allies. Iran is “behind the entire axis of terror” that threatens the U.S. and Israel, he said, speaking at a memorial for late former Sen. Joe Lieberman.

Knickmeyer, Amiri and Khalil write for the Associated Press. AP writers Stephen Groves, Mary Clare Jalonick and Alanna Durkin Richer contributed to this report.