The basic question is this: By saying that a division of territory between Israel and Palestine should be “based on” the “1967 lines” between Israel and the West Bank, with agreed “swaps” of land, did Obama move beyond the previous U.S. position on the subject?

The short, technical answer to this question is: no. The longer, political response is that by stating the principle, Obama gave a boost to Palestinian President Mahmoud Abbas, who has tried to make Israeli acceptance of it a condition for peace talks, and a slap to Israeli Prime Minister Binyamin Netanyahu, who has resisted it.

That Obama would do this on the eve of Netanyahu’s arrival in Washington for a White House meeting — and apparently without warning the Israeli leader — is a gaffe that has understandably angered Netanyahu and many of his U.S. supporters.

First, let’s go to the policy wonk discussion. The facts there are pretty clear: ever since the Israeli-Palestinian peace talks at Camp David in 2000, Israelis, Palestinians and Americans have talked about a Palestinian state that starts with the Gaza Strip and West Bank (the “1967 lines”), but adds West Bank territory to Israel in order to annex the largest blocs of Jewish settlers, and compensates Palestine with territory that now is part of Israel.

The settlement “parameters” drawn up by President Bill Clinton in late 2000 (and approved by the then-Israeli cabinet) called for Israel to annex about 5 percent of the West Bank in exchange for giving Palestine 3.5 percent of Israeli territory, plus a corridor connecting the West Bank with Gaza.

President George W. Bush adopted this same formula. In 2004 he gave then-Prime Minister Ariel Sharon a letter saying that the United States recognized that Israel would not return to the 1967 lines and that it would annex large settlements near its borders. But Bush also declared after a 2005 meeting with Abbas that U.S. policy was that “changes to the 1949 armistice lines must be mutually agreed to.” Since the 1949 lines are the same as the 1967 lines, Bush was, like Obama, saying that the old lines would be the starting point.

I asked a former senior adviser to Bush whether he could identify any difference between Bush’s formula and Obama’s. Other than the fact that Bush used the date 1949 rather than 1967, the adviser offered the argument that Bush, unlike Obama, explicitly stated that Israel would never return to its 1967 borders. But it is implicit in Obama’s formula of “swaps” that Israel will not go back to the old lines — and in an interview Thursday with the BBC Thursday the president made it explicit: “Negotiations will involve looking at that 1967 border, recognizing that conditions on the ground have changed and there are going to need to be swaps,”he said.

So the idea that Obama has proposed that Israel “return to the 1967 borders,” as various GOP hopefuls are claiming, is simply untrue.

That doesn’t mean that Netanyahu doesn’t have reason to be fuming as he heads for his meeting with Obama today. For months, Washington has been privately pressing the Israeli leader to endorse the 1967-lines-principle as a way of jump-starting moribund talks with Abbas. Netanyahu has resisted, though he inched toward the position in a speech last Monday. Now Obama has publicly sprung the principle on him — even though there is next to no prospect that negotiations can be started anytime soon.

In the end this looks like another instance in which Obama’s insistence on pushing his own approach to the peace process will backfire. The president was urged by several senior advisers not to delve deeply into Israeli-Palestinian affairs in this speech, just as he was warned last year not to continue insisting on a freeze of Israel’s West Bank settlements. Apparently at the last minute, Obama chose to include the 1967-lines idea in his speech. The result has been the draining of attention from the speech’s central discussion of Arab democracy, a cheap talking point for GOP opponents — and yet another pointless quarrel with Bibi Netanyahu.