BBC security correspondent Frank Gardner examines the impact that the killing of Sheikh Ahmed Yassin may have on al-Qaeda and the Bush administration's war on terror.
Q: Is there a link between al-Qaeda and the the political situation in Israel and the Palestinian territories?
Osama Bin Laden never historically had a great deal of interest in the Palestinian-Israeli question.
If you talk to Abdul Bari Atwan, for example, the editor of al-Quds al-Arabi newspaper, he is a Palestinian and he met Osama Bin Laden in the 1990s and he says Bin Laden never mentioned Palestine once - he wasn't interested.
His big beef then was getting American forces out of Saudi Arabia.
But that happened months ago, and al-Qaeda has very successfully been able to jump on the bandwagon of Arab anger over the denial by Israel of a Palestinian state. Now I think we are going to see an increase in links between various networks in the Middle East.
Q: How are al-Qaeda or its sympathisers likely to react to the killing of Sheikh Yassin?
The killing of Sheikh Ahmed Yassin will play right into al-Qaeda's hands, even though there is no proven link between al-Qaeda and Hamas.
This will go down very badly in the Middle East. It will allow al-Qaeda to say to its supporters and sympathisers, "look this is just another example of how the West and its ally Israel is trying to oppress Muslims".
And remember that for most Arabs and Muslims, the Hamas movement was one of national liberation from occupation, that's how they perceive it, they don't see it as a terrorist movement in the way that the West does.
Q: How was Sheikh Yassin regarded in the region?
He was primarily a Palestinian figure. Obviously, as a quadriplegic he had no physical part in any acts of violence, but the Israelis certainly considered him as one of the main inspirations behind acts of violence.
He was respected by many people because for a start, as an older man, as a sheikh, as a learned man. He had quite a degree of respect that went well beyond the borders of the Palestinian territories.
Q: Will his death provoke unrest elsewhere?
So he had his followers in the Gulf and Egypt and elsewhere. This will be deeply unpopular in many parts of the Arab world.
But I don't think we're going to see the overthrow of governments because of it. People tend to exaggerate the reaction these sorts of things.
There will be a period of anger and it will increase the risk in the short term to Israeli's and possibly to western interests in the region.
Q: What kind of man was he?
On a personal level he was quite engaging. I interviewed him a couple of years ago from his hospital bed in Gaza. He didn't speak English, he spoke only Arabic.
He was one of those people that thought very carefully before he opened his mouth. He was a tiny, frail man, but his influence and prestige was enormous within the Palestinian territories.
He was the spiritual leader of Hamas, a very powerful organisation with international links.
Q: What is the US view of Israel's policy and tactics against Palestinian militants?
What I have found from my personal experience is that people in the US state department tend to have a very good understanding of the problems of the Middle East and why al-Qaeda is so popular and they tend to steer a relatively middle course.
People closer to the White House and the defence establishment tend to take a much more hard-line view, and you've only go to look to the comments by Dick Cheney where he says "there's only one way to deal with terrorists and that's to root them out and destroy them", to see that.
I don't think Britain takes such a straightforward view, I think certainly the British government realises that there are grey areas.