I’ve been unable to find another instance when an American political party allied itself so closely with a friendly foreign government for the purpose of defeating the policy of an American administration.There is no more outspoken foe of the Iran nuclear deal backed by the Obama administration than Prime Minister Benjamin Netanyahu, nor has there ever been a leader of an American ally who has plunged so deeply into domestic partisan American politics. In the process, Netanyahu has put the final nails in the coffin of pro-Israel bipartisanship and driven a huge wedge into the heart of the American Jewish community. In the end, his efforts are unlikely to undo an Iran pact he claims to be a mortal threat to the Jewish state – although much of his own security establishment disagrees.The Netanyahu-Republican alliance isn’t new. It dates back to the Clinton administration when Netanyahu, the leader of the Likud opposition, and House Republican leader and later speaker Newt Gingrich worked closely to foil the peace policies of prime ministers Yitzhak Rabin and Shimon Peres. A common denominator is Ron Dermer, a Gingrich aide in the 1990s and now Netanyahu’s ambassador to Washington.Republicans are in virtual unanimous opposition to the Iran deal, and I have no doubt that wouldn’t change even if the ayatollahs agreed to total disarmament, recognized Israel and joined the Tea Party. The deal, notwithstanding its faults and strengths, is virtually a side issue; this is more about Republican hatred of Obama and wanting to defeat his major foreign policy achievement.They tried and failed – so far – to kill Obamacare, losing twice to a conservative-dominated Supreme Court, and they’ve voted unsuccessfully more than 50 times to repeal it and still are yet to vote on the viable replacement they’ve been talking about.This GOP-Netanyahu affair is not because Republicans love Israel more than Democrats do, though that is a lurking danger. Reliable polls show rank-and-file American Jews support the deal, unlike mega-wealthy contributors, major organizations and their leaders.Netanyahu’s battle has opened up deep divisions within the Jewish community that could take years to heal, if that. Nowhere was that clearer than in the vicious attacks on Rep. Jerry Nadler (D-New York) for having announced his intention to vote for the deal.The 13-term Jewish congressman, whose Brooklyn-Manhattan district has the largest Jewish population in the country, was called a “kapo” – Jews who collaborated with the Nazis – by one commentator. Another said he had “facilitated Obama’s holocaust.”Nadler’s Democratic colleagues, although on the other side of the issue – Senator Chuck Schumer and Representatives Eliot Engel, Nita Lowey and Steve Israel – quickly denounced the “egregious” and “malicious” attacks on Nadler and the rising vitriol in the debate. Obama called the attacks on Nadler “appalling.” Netanyahu has been silent. The divisions are exacerbated by the intense lobbying campaign piloted by the American Israel Public Affairs Committee (AIPAC). It is investing upwards of $40 million, by its own boasts, to defeat Obama’s Iran agreement, which America’s five negotiating partners have already approved.After a summer of big spending, flying members of Congress to Israel to be lobbied by Netanyahu and his government and sounding like Netanyahu’s other Washington embassy, the organization could find itself facing not only charges of dual loyalty but, more critically, a Department of Justice investigation of possible violation of Foreign Agents Registration Act.The law requires persons acting as agents of foreign principals in a political capacity to register with the Justice Department and provide detailed public disclosure of all contacts in any part of the US government, income, expenditures and relationships with its foreign principal.If AIPAC were deemed a foreign agent it would lose its tax-exempt status and more importantly its claim to be an American lobby representing the American Jewish community.That would likely narrow its fundraising base and hobble its role in political campaigns. AIPAC may be barred from formally controlling or coordinating the PACs (political action committees, which collect and distribute campaign contributions) – but it is no secret that those and many Jewish groups and activists look to AIPAC for guidance in supporting candidates.AIPAC’s longtime affinity for Likud and the GOP has seen a deterioration of Democratic support, and it is bound to worsen after this summer’s Iran campaign. Since Republicans are unanimously opposing the agreement, the lobby group has focused on persuading Democrats to vote against the leader of their party, their president. The message is Obama is undercutting American security and endangering Israel.Republican leaders concede they won’t have the votes to override a presidential veto of their resolution disapproving the agreement, but they’re sure to get a solid majority in both houses and will be using that against Democrats in next year’s elections.That’s understandable, but what is puzzling is why AIPAC and Netanyahu fail to appreciate the damage they’re doing to themselves and to Israel.The anti-Obama campaign may well drive more and more Democrats away from Israel, and that will haunt AIPAC when this is over and its lobbyists go to the Democrats for help on other issues.In the short term, because of AIPAC’s influence on political contributions, change will come slowly, but it is coming. Jews won’t migrate to the GOP, which is far too conservative for the vast majority – especially in this Year of the Donald – but many, especially the Left and the young, are likely to simply drift away.“The damage Bibi has done to the US-Israel relationship is nearly incalculable. The damage he has done within the US Jewish community is a catastrophe of historic proportions,” said David Lachmann, a Hill veteran and former Nadler staffer.Amos Yadlin, the former head of IDF military intelligence and now director of Israel’s Institute for National Security Studies, is the latest prominent military and intelligence figure to urge Netanyahu to stop attacking an agreement he can’t prevent and begin repairing bilateral relations.He said Israeli government “should avoid interfering” in the US internal debate and he called on the prime minister to instead open a “constructive dialogue” with American leaders on how to live with the nuclear agreement.Citing Obama’s letter to Nadler saying the administration intends to strengthen Israel and the strategic relationship, Yadlin proposed a “parallel agreement” providing “a suitable response to future dangers inherent in the agreement with Iran.”His message for Netanyahu is simple: once you find yourself in a deep hole, stop digging and start looking for a way out.