You might think Fatah is the real equivalent of the IRA (or more appropriately Sinn Féin), but they are extremely corrupt and have been fully coopted by the Israeli government. The Palestinians elected Hamas because their lives weren't getting better under Fatah. If you think they did it because they're extremists who want the Israelis destroyed, first of all you're a racist, and second of all you need to read the exit polls from the 2006 election and Hamas's new charter.
The US and Israel deliberately sabotaged attempts by Fatah and Hamas to form a government and actually govern. Just like the US always does when an election in an unstable country with lots of oil doesn't go how it wants.