When 5,000 AIPAC activists ascended Capitol Hill this week, they pushed a multifaceted agenda with a clear bottom line: It’s the sanctions, stupid.

The lobbying trek that traditionally follows the annual AIPAC policy forum addressed the role of Arab nations in advancing Israel-Arab peace and sought to secure a pledged increase in U.S. assistance to Israel.

But the most dramatic advance was a proposal to cut off refined petroleum exports to Iran, hitting 40 percent of that country’s gas market.

AIPAC has led the way since the mid-1990s in advocating for sanctions aimed at crippling the Iranian economy until the Islamic republic ends its suspected nuclear weapons program. In recent years, the notion of sanctioning Iran has gained traction, with the United Nations Security Council imposing three sets of sanctions in the past 18 months.

Still, the sanctions have apparently had little effect: U.N. nuclear weapons inspectors delivered a blistering report last month, saying that Iran was taking steps to hide its weapons program. In addition, inspectors say they have evidence suggesting that some elements of the Iranian program were military and not peaceful — in sharp contrast to Tehran’s claims.

After two days of sessions that addressed the possibility of a nuclear threat, 5,000 of the 7,000 activists in attendance headed to 500 meetings on Capitol Hill. They were armed with supportive talking points about a bill that has languished in the Senate since it passed overwhelmingly in the House of Representatives last year.

The Iran Counter Proliferation Act would expand existing sanctions by hitting companies and nations that deal with Iran’s energy sector. It also would cut off Iran entirely from the U.S. finance system.

Bolstering that bill is a nonbinding resolution put forward last week by Reps. Gary Ackerman (D-N.Y.) and Mike Pence (R-Ind.). The resolution urges President Bush to immediately impose some of the sanctions in the Counter Proliferation Act and adds the new proposal: cut off the export of refined petroleum to Iran.

“Despite sitting on some of the largest oil reserves in the world, Iran has been forced to import 40 percent of its refined petroleum — gasoline and diesel — because of a lack of investment in its oil refining infrastructure,” states the memo prepared for AIPAC activists. “Limiting Iran’s ability to import gasoline will severely impact Iran’s economy and could lead to dramatically greater domestic pressure on the regime to change course.”

The language of the congressional resolution is sensitive to the political realities of a presidential campaign that has made the possibility of war against Iran a partisan issue: It explicitly counts out military action.

The proposal falls just shy of reported suggestions from Israel’s government that the United States and Britain blockade Iran’s ports to keep out refined petroleum. Israeli Prime Minister Ehud Olmert reportedly brought up the proposal in conversations last month with House Speaker Nancy Pelosi (D-San Francisco).

AIPAC talking points — especially when it comes to Iran — generally are careful to hew to areas where Democrats and Republicans agree. However, some of the language would appear to clash with specific policies associated with Sen. Barack Obama (D-Ill.).

“Entering into a dialogue before Iran has complied with U.N. resolutions and suspended its uranium enrichment could undermine Security Council decisions and allow Tehran to use the dialogue as a way to continue advancing its nuclear program,” the AIPAC memo states.

Also on the lobbying agenda was Bush’s proposal to increase U.S. assistance to Israel from $2.4 billion to $3 billion annually.

Letters circulating in both chambers of Congress urge the president to continue his efforts to advance the Israeli-Palestinian peace process. The letters, initiated in the House by its leaders, and in the Senate by Mary Landrieu (R-La.) and Susan Collins (R-Maine), do not mention recent backing by Bush and Congress for increased U.S. financial and political support for Palestinian moderates. Instead they decry the alleged lack of such support from Arab nations.