"Why" isn't a question that needs to be asked or answered right now. The fact of Israel's unique standing in the Middle East is the matter in need of underscoring. Israel's and the United States' long-standing cordiality -- a condition the president is not precisely promoting by leaning on Benjamin Netanyahu instead of the terrorist gang Hamas -- is based only partly on the solidarity of American Jew with Israeli Jew. It is based only partly on the perception of particular evangelical Christians that the convergence of the Jews in Judea and Samaria somehow betokens fulfillment of biblical prophecies.
A bigger reason for the cordiality of which I speak concerns basic values. Israel's civic values are recognizable as Western values -- love of freedom, dislike of tyranny; willingness to lay lives on the line in defense of both values.
Americans who favor the Palestinian side in Middle Eastern controversies over Israeli settlements on the West Bank and the like generally belong to the political left. They don't themselves particularly like the traditional America. They less prefer the American "exceptionalism" that so much resembles Israeli "exceptionalism."
It's Israel's enemies and critics on whom we ought to keep our gaze as we evaluate the president's proposals. Not many of these critics are of the old, irrational anti-Semitic right.
More noticeable are the kind -- you see them in left-wing religious circles and in hard-core secular environments -- who rarely have a good word to say for Western history or Western values; who tend to view the United States as a sinister presence abroad, doing more harm than good.
To such as these, Israel and America are two of a kind. Come to think of it, maybe they're right. If so, we should do something about it -- such as make sure our kind doesn't diminish any further.