But there are still some unanswered questions to me
1: Why the FBI HQ resisted opening a broader investigation after it catched Moussaoui?
2: Why did the government’s Justice Department plus top FBI officials blocked an FBI request for a national security warrant to search Moussaouis laptop?
3: Why Ashcroft has been advised to travel only by private jet instead of commercial airlines a few days before 9/11?
4: Why there was no reaction to the very precise warnings of several foreign intelligence (Israel, Russia, Egypt, France, British, Jordan) ?
1: Why the FBI HQ resisted opening a broader investigation after it catched Moussaoui?
Why the assumption that they have not? Just because it doesn't make it to the top CNN's Headline news, does not mean it is happening. Effective counter-terrorism rely on secrecy. Terrorists watch the news for information. If one of theirs gets caught, they pay close attention. To avoid sending them all to ground, investigators will try to keep as much from the media as possible. Make no assumptions in this regard.
2: Why did the government’s Justice Department plus top FBI officials blocked an FBI request for a national security warrant to search Moussaouis laptop?
I don't know anything about this. But since FBI is part of the Justice department, your question seems a bit confused. which part of the Justice department denied FBI? could be adepartmental turf battle, or an attempt to keep information compartmentalized and keep it off the evening news where it could tip off Moussaouis confederates. Remember, the FBI is still suffering from it's reno/clinton hangover and there have been several leaks of sensitive information for political purposes without regard to national security concerns.
3: Why Ashcroft has been advised to travel only by private jet instead of commercial airlines a few days before 9/11?
I don't know that he was. But this sounds a lot like the Micheal Moore claims that members of the Saudi Royal Family and Bin Ladens reletives were cleared to leave the U.S. before u.s. airspace was re-opened to the general public after 9/11. Claims which turned out be false, in spite of being picked up by the mainstream media.
4: Why there was no reaction to the very precise warnings of several foreign intelligence (Israel, Russia, Egypt, France, British, Jordan)?
Exactly which warnings are you talking about? When were these issued and what source?