The threat of Iran developing a nuclear weapon dominated the annual policy conference of the American Israel Public Affairs Committee (Aipac), which was attended by a record 13,000 participants from every state in the US, and a number from other countries.

Speaker after speaker called for America to take effective measures to counter the threat, including by military action if necessary. The standing ovations — a feature of American political life — came thick and fast.

“President Barack Obama is not bluffing,” Vice-President Joe Biden told the conference. “We are not looking for war. We are looking to and ready to negotiate peacefully. But all options, including military force, are on the table.”

Mr Obama and Israeli Prime Minister Benjamin Netanyahu may not have attended because they are expected to meet in Israel in two weeks, but the event still had plenty of heavyweight speakers and serious business was accomplished.

On Monday, good news came from the US House of Representatives: two lawmakers, one Democrat and one Republican, had introduced a bill that would designate Israel, uniquely, a “major strategic ally” of the US.

If passed, the bill will formalise a number of facets of the US-Israel relationship, including annual defence assistance and co-operation. The bill could assume even greater significance in heading off possible cuts to US military aid to Israel that might result from US legislators’ failure to pass a budget.

As usual, the diaspora’s largest gathering of Israel supporters was run with consummate slickness and unashamed razzmatazz. The vast arena faced bright and hard-hitting video displays that changed constantly. The Stars and Stripes and Israel’s blue Star of David rippled across the screen as the audience, many with hand on heart and tears in their eyes in traditional US fashion, roared out the Star Spangled Banner and Hatikvah.

But there was a serious aim to it all: the conference concluded with participants heading to Capitol Hill to lobby all 100 Senators and every member of the House of Representatives.

Chief Rabbi Lord Sacks was one of the hits of the conference. Addressing 2,500 of Aipac’s financial supporters, he said that at stake in Israel’s survival was the future of freedom itself and got a standing ovation.