Last week, John Kerry negotiated with Hamas (via their financial ally Qatar). He eventually presented a proposal of which liberal Israeli newspaper Haaretz said, "It might as well have been penned by Khaled Meshal. It was everything Hamas could have hoped for. "
Here is what Obama said in 2008 to court the Jewish vote, asserting that Hamas should not be negotiated with until they recognized Israel's right to exist:
The first job of any nation state is to protect its citizens. And so I can assure you that if -- I don't even care if I was a politician. If somebody was sending rockets into my house where my two daughters sleep at night, I'm going to do everything in my power to stop that. And I would expect Israelis to do the same thing.
In terms of negotiations with Hamas, it is very hard to negotiate with a group that is not representative of a nation state, does not recognize your right to exist, has consistently used terror as a weapon, and is deeply influenced by other countries. I think that Hamas leadership will have to make a decision at some point as to whether it is a serious political party seeking to represent the aspirations of the Palestinian people. And, as a consequence, willing to recognize Israel's right to exist and renounce violence as a tool to achieve its aims. Or whether it wants to continue to operate as a terrorist organization. Until that point, it's hard for Israel, I think, to negotiate with a country that -- or with a group that doesn't recognize Israel's right to exist at a country -- OK.