Caroline Glick is one of the sharpest analysts around. Her columns in the Jerusalem Post are always worth a read.
In this essay published on her personal blog, Caroline reviews the Obama administration's Israel policy and goes into great detail in refuting its major tenet; that US national interest demands that we distance ourselves from Israel:
Today, as the Obama administration is openly distancing the US from Israel while giving the impression that Israel is a strategic impediment to the administration's attempts to strengthen its relations with the Arab world, recalling why Israel is the US's most important ally in the Middle East has become a matter of some urgency.
Much is made of the fact that Israel is a democracy. But we seldom consider why the fact that Israel is a representative democracy matters. The fact that Israel is a democracy means that its alliance with America reflects the will of the Israeli people. As such, it remains constant regardless of who is power in Jerusalem.
All of the US's other alliances in the Middle East are with authoritarian regimes whose people do not share the pro-American views of their leaders. The death of leaders or other political developments are liable to bring about rapid and dramatic changes in their relations with the US.
[...]America reaps the benefits of its alliance with Israel every day. As the US suffers from chronic intelligence gaps, Israel remains the US's most reliable source for accurate intelligence on the US's enemies in the region.
Israel is the US's only ally in the Middle East that always fights its own battles. Indeed, Israel has never asked the US for direct military assistance in time of war. Since the US and Israel share the same regional foes, when Israel is called upon to fight its enemies, its successes redound to the US's benefit.