Prime Minister Ehud Olmert and Palestinian Authority Chairman Mahmoud Abbas are, to borrow the language of a mechanic, putting the pedal to the metal on a car sitting high up on a hydraulic jack. In other words, it's full gas in neutral. As swell as it might be that Olmert and Abbas are holding these talks, all the optimism and good cheer and willingness to revisit what are essentially the Clinton parameters of 2001 cannot paper over two fundamental issues that both leaders prefer to ignore. The first is that even if Olmert and Abbas reach an "agreement of principles" dealing with the core issues - Jerusalem, borders and the refugees - neither of them is strong enough politically. Olmert and Abbas need to discuss these issues, because that is what the US wants them to do in order to serve its wider Middle East goals of forging a "moderate coalition" to help out in Iraq and to face off against Iran. But Olmert and Abbas can't implement any agreement on these issues because they cannot deliver their publics. Abbas does not rule Gaza, and his grip on the West Bank is not all that tight. So even if - for the sake of argument - he would agree that Palestinian refugees or their descendents will have the right to return to a Palestinian state, but not to Israel, what would it really matter, since Hamas - which controls Gaza and does what it pleases - would never assent? And even if Olmert would agree to cede Arab neighborhoods of Jerusalem and to share sovereignty over the Temple Mount, as is reportedly being discussed, what would it really matter since he could never get this through the Knesset? A lot has happened since these ideas were raised during the twilight of the Clinton and Barak administrations in 2001. The Israeli public, following seven years of unrelenting terror, is - according to all opinion polls - not in the same giving mood that it was before the onslaught of Palestinian violence that began in September 2000. While Ariel Sharon, when he was prime minister, was able to push disengagement through a reluctant Knesset because he enjoyed widespread popularity and because he knew that the legislature would buckle in to public opinion, Olmert - by contrast - has neither a strong Knesset coalition nor popular support. And the second fundamental issue that both leaders seem to be merrily ignoring is Hamas's control of Gaza, and all that implies. The major challenge facing both Olmert and Abbas is not producing a paper that will please US Secretary of State Condoleezza Rice, but rather what to do with Hamas - Iran's new local proxy. Any agreement that Olmert and Abbas might work out will be meaningless if Hamas retains its current strength in Gaza. The key issue right now - even more so than the "fundamental" issues of Jerusalem, borders and refugees - is what to do with Hamas, how to stem its Hizbullah-like buildup in Gaza. Because unless Hamas is properly defanged, either by Israel, the PA or a combination of both, it will retain its ability to scuttle any agreement through terrorist actions. The deputy head of the Shin Bet warned at the cabinet meeting on Sunday that Hamas may carry out terrorist attacks here or abroad to try to scuttle the current diplomatic initiatives. The Olmert-Abbas-Rice strategy of "a political horizon" seems somewhat simplistic, with the idea being that if you just show the Palestinians a skeleton of a potential agreement, then they will eject Hamas and hop on board the peace train. But what if they don't (as they didn't in the past when this same political horizon was offered by Clinton and Barak), or what if Hamas simply doesn't let them. By agreeing to discuss Jerusalem, refugees and borders now - despite the road map, which makes clear that these issues should not be discussed until a later stage - Olmert is saying that dancing around the core issues does nobody any good. He might be right. But what he is ignoring is that since the Hamas takeover of Gaza, Hamas and Gaza are right now the most important core issue, if only because Hamas can hold everything else hostage. For instance, imagine how successful Tuesday's summit would have been had the Kassam rocket fired from Gaza that day actually killed somebody when it slammed into Eli Sabag's home in Sderot?