Ariel Sharon went up to the Temple Mount to inflame the Palestinians because he knew this would create an outburst of violence that would further his goal of achieving state power for himself in his role as "tough guy."
He wanted state power so he could further his ultimate political goal of Eretz Ysrael or Biblical Israel--Israel roughly from Lebanon to the Sinai and from the Mediterranean to the Jordan River. This is a goal favored by Sharon and some members of the Likud and some of the ultra-orthodox parties, but not by all Israeli Jews (e.g., Shimon Peres et al.)
Sharon is now on the verge of achieving Eretz Ysrael, by effectively declaring war on the Palestinian Authority, even though he knows that the PA and Arafat do not and cannot control Hamas and the other organizations behind the suicide bombings.
This is, as some have pointed out, the end of the "two state solution" favored by President Bush. I think this is unfortunate, because the Palestinians have as much right to be in that area as the Jews, and when you have a situation like that, the only answer is a two-state solution.
The result of the latest move by Sharon will be greater threats of terrorism not only to Israel, but to the US, since people throughout the Moslem and Arab world hold the US responsible for the actions of Israel.
In other words, Sharon is not a hero, but a fanatic, who is making the entire situation worse, not better. Instead of going after the Palestinian Authority, he should go after Hamas, the Popular Front for the Liberation of Palestine, and the other organizations that are directly responsible for the bombings. If Mossad and Shin Bet are so good, surely they could do this.
Immediately following the bombing, Israeli TV announced that an anonymous call came from Islamic Jihad claiming responsibility for the attack.