The terrorist threat Israel faces is the same terrorist threat the US faces. Every single terror group Israel fights against has in its agenda the murder of Americans. The US, if it wishes to stick to its principles, should support Israel's war on terrorism, when it comes specifically to the Palestinian Authority, of whom we have diplomatic relations with.
Arafat may have been terrorizing the Israelis for God knows how long but Bin Laden killed Americans. I would not base anything as factual from your Israel biased paper as "evidence". Frankly I think avenging the deaths of nearly 3,000 Americans and counting is a higher priority than a speculative case at best that Arafat killed 3 Americans.
This is a war against all Islamic terrorism, not just who was responsible for 9/11. Al Queda is not the only terrorist group in the world which has murdered Americans. Every terrorist group must be targetted. Arafat and his terror groups have murdered dozens of Americans, not just these three. Remember the Hebrew University bombing in 2002? 5 Americans were murdered there. Of course Al Queda, by sure quantity of Americans murdered, should be a priority. No one is telling America to send troops to Gaza, as Israel is capable of doing what is needed.
It is not just about avenging the deaths, its also about making sure another attack like this doesn't happen. For that not just Al Queda is being fought by the US. Arafat and the Palestinian Authority, and those terror groups under him, are enemies of the United States, have no doubt.