One of the remarkable things about Israel in the realm of U.S. foreign policy is that it stands above the rest of the international terrain. The Zionist project is supreme and comes before all other considerations and contenders for U.S. attention. This has remained a constant since 1970 and regardless of the actions of a particular Israeli government.
The investigative reporter, Seymour Hersh, wrote a book in 1991 about the development of atomic weapons by Israel, The Samson Option. Well worth reading and bursting with little known facts, this book describes the deliberate effort by each U.S. administration to look the other way in spite of information that would have allowed the U.S. to insist on a stop to nuclear weapons development by Israel. Then, with the nuclear weapons developed, Israel was able to force the United States to send it conventional weapons during the 1973 war by threatening to use those nuclear weapons against the Arabs if the U.S. did not come through. Did this change U.S. policy toward Israel? No.
The reason for this is, as always, the political might of the Israel lobby in the United States and the influence of wealthy donors at the highest levels of the U.S. government. Hersh's story of Abe Feinberg is a perfect example of a fund-raiser so powerful that he is called in before political decisions are made to see if a possible policy change would be acceptable to the lobby.
Also in the book is a detailed account of the espionage of Jonathan Pollard, an American who sent over 500,000 pages of classified U.S. intelligence material to Israel and with the knowledge by Israeli leadership that it was taking place and should continue. Most incredible is that Israeli PM Yitzhak Shamir turned over some of the information to the USSR in an attempt to thaw relations between Israel and Russia.
This kind of double dealing is to be expected between nations. What makes the Pollard/Israel case exceptional is that there were no consequences for Israel. Though Pollard was given life in prison, it was still possible to mount a "free Pollard" movement in the U.S. that continues today. At one time, some synagogues had signs up demanding Pollard be freed - U.S. citizens asking that a traitor to the United States be freed! Were Americans in general upset by this? No.
The very idea that the U.S. would even consider freeing a person caught undermining the country with determination for years (Pollard sent everything he could get his hands on) is evidence that Israel is not just another country, but an exception for which the U.S. will jump through hoops. But we know that. And we know it continues to this day, as we see President Obama and Secretary of State Clinton virtually beg Israeli PM Netanyahu to stop settlements - then stand by helplessly when he doesn't.