WASHINGTON — US Vice President Joe Biden came directly to the J Street conference in Washington, DC, from a one-on-one meeting with Prime Minister Benjamin Netanyahu. He brought with him a no-nonsense message that emphasized Washington’s support for Israel’s security and a strong stance against Iran. The message might have been coolly received had it been delivered by someone else, but J Street’s largely Democratic supporters welcomed the vice president like a rock star.

Biden, the highest ranking US official to ever address the conference, was introduced by former US ambassador to the UK Louis Susman, who told attendees that Biden was someone who “shares your values.”

“If he wasn’t of Irish stock he would probably be Israeli,” he joked to an audience that jumped to its feet and cheered enthusiastically when Biden took the stage.

Biden’s announcement that he had come straight from seeing Netanyahu was greeted by another round of applause. But an audience thirsty for details on the peace talks was left parched for the majority of the speech.

The vice president acknowledged he was speaking to a crowd that was largely comprised from his party’s progressive base. “There is no contradiction between being progressive and being a supporter of Israel,” he said to another round of applause.

But when he entered the meat and potatoes of his talk, Biden sounded much more like a hawk than a J Street-style progressive.

“A nuclear armed Iran would pose an existential threat to Israel, an unacceptable danger to world peace and security, including the likelihood of a nuclear arms race in the Middle East, making everyone less secure,” Biden warned.

“We don’t know if Iran is willing to do what is necessary to get there, but we, along with the Security Council and Germany (the so-called P5+1), are willing to find out.”

The test, Biden said, “is meaningful, verifiable and transparent actions by Iran.”

The vice president stressed that the US-led sanctions on Iran’s economy were the most effective sanctions regime ever.

“America’s support for Israel’s security is unshakable,” Biden declared, talking up military aid and the Iron Dome rocket defense system.

“Israel’s long-term security depends on a just and lasting peace,” Biden asserted and then launched in to a long tale about meeting a chain-smoking prime minister Golda Meir and Yitzhak Rabin when he was a young senator, shortly before the 1973 Yom Kippur War.

Biden only returned to the topic of the peace process after a dissertation on the divisions between Sunni and Shi’ite Islam. He declared to silence that Israel must remain a Jewish state, but was greeted by ringing applause when he continued that the state of Palestine would be for the Palestinian people.

The vice president said that the Arab Spring had created an urgent impetus for advancing the peace process. In an environment of growing extremism, he argued, “the Palestinian-Israeli issue involves the least ideological and least sectarian Arabs in the Middle East.”

Conference attendees were mostly unimpressed by the speech, which a number characterized as reminiscent of an address made for AIPAC audiences.

“He mentioned Palestine as a state – that is really rare,” enthused one attendee.

Another, however, complained that Biden had “brought his AIPAC speech,” referring to the more-hawkish Israel advocacy powerhouse.

In the midst of Biden’s speech, as Twitter feeds filled with comments as to the hawkishness of Biden’s speech, J Street tweeted that Biden’s message was that “military strength important, but diplomacy is stronger.”