What does Obama's stand on the 1967 borders achieve?
President Barack Obama's tough line on the Middle East peace process may do more to convince people in the Arab world that America is on their side than all the talk of comparing their uprisings to the Boston Tea party or Rosa Parks' civil rights protest.
American presidents have talked before about the 1967 borders.
In one sense it is obvious that any Palestinian state will be based on Gaza and the West Bank, the lands occupied by Israel after the Six Day War.
But what Mr Obama has just said is new.
Negotiations are often more about the sequence in which things happen rather than the end point. He has said agreement about the borders should be the basis for talks - not their conclusion but their starting point.
In an exclusive BBC interview with Andrew Marr, to be broadcast in its entirety on Sunday, the president explained his thinking.
"Our argument is, let's get started on a conversation about territory and about security," he said.
"That doesn't resolve all the issues - you still end up having the problem of Jerusalem and you still end up having the problem of refugees - but if we make progress on what two states would look like and a reality sets in among the parties that this is how it is going to end up, then it becomes easier for both sides to make difficult concessions to resolve those two other issues."
Mr Obama may be known for his cool but there seemed icy irritation at the lack of progress.
He said: "The international community is tired of an endless process that never produces an outcome."
It is hard to believe he was not riled by the Israel prime minister giving the go ahead for more settlements when he had called for them to stop.
The leading - if undeclared - Republican presidential candidate, Mitt Romney doesn't like it.
He said: "President Obama has thrown Israel under the bus. He has disrespected Israel and undermined its ability to negotiate peace. He has also violated a first principle of American foreign policy, which is to stand firm by our friends."
The Israeli prime minister didn't like it.
His office issued a furious statement: "Prime Minister Netanyahu expects to hear a reaffirmation from President Obama of US commitments made to Israel in 2004, which were overwhelmingly supported by both houses of Congress.
Among other things, those commitments relate to Israel not having to withdraw to the 1967 lines which are both indefensible and which would leave major Israeli population centres in Judea and Samaria beyond those lines."
The Simon Wiesenthal Center expressed deep disappointment, saying, "a return to 1967 borders as the basis for negotiations, even with 'land swaps' is a non-starter, when at least half of the Palestinian rulers are committed to Israel's destruction".
There is positive reaction too, of course.
But this is tough stuff, hard to swallow for the current Israeli government. So what does it achieve?
It is hard to see how it makes talks more likely. Perhaps it casts Mr Netanyahu as part of the problem, as yesterday's man. Maybe it will play a part in dissuading the Palestinians from demanding what Mr Obama called a "symbolic" vote on independence at the United Nations.
It does put Mr Obama on the side of the Arab Street more eloquently than his declaration that backing democracy is America's top priority (funny that Saudi Arabia didn't get a mention).
But perhaps above all it fits with his post-Bin Laden projection as a hard-headed risk taker.