Gary Silow, a Philadelphia-area lawyer and Aipac member at the convention, said he was deeply troubled by the potential for renewed discussion of what he said was the offensive “dual loyalty” issue. In Mr. Silow’s view, “the fact that they came after Aipac was what was really disturbing.”

Like many at the convention, Mr. Silow said he was relieved at the move for a dismissal.

More than half the members of the House and Senate attended Monday night’s dinner, which featured the group’s “roll call” in which the lawmakers all rise. It is a conscious  and effective  effort to demonstrate the group’s influence on Capitol Hill.

Even as the charges were dismissed, the issue of Aipac’s role in the capital’s political life surfaced again in recent days with the disclosure that Representative Jane Harman, Democrat of California, had been overheard in 2005 on a government wiretap offering to help reduce the charges. Ms. Harman, who has denied she intervened in the Rosen-Weissman case, was greeted with sustained applause when she appeared on Sunday morning.

The site of the conference, the Washington Convention Center, is conveniently, and symbolically, about equally close to the White House and the Capitol, the two objects of Aipac’s muscular demonstration. Along with 6,000 delegates, mostly Jewish, leaders of the two branches of government have been attending the convention to offer praise for Aipac and support of Israel, both in generally unreserved language.

The roster of scheduled guests from Sunday through the meeting’s conclusion on Tuesday included Vice President Joseph R. Biden Jr.; Senator John Kerry, the Massachusetts Democrat who is chairman of the Foreign Relations Committee; Newt Gingrich, a former House speaker who remains an important Republican voice; and Rahm Emanuel, the White House chief of staff, who has longstanding ties to Israel. The group also heard from the new Israeli prime minister, Benjamin Netanyahu (via satellite), and the new opposition leader, Tzipi Livni, and the president, Shimon Peres (in person).