It is very common for people to believe that 9/11 was purely a terrorist attack. That is because it is hard to believe that some people could be so evil that they planned this all. It is easier to believe in crazy people in a desert.

That is until you you look deeper.

How many trillions of dollars did they get out of this?

Direct evidence of demolition or criminal acts:
1) The 3 towers fell free-fall speed. Which impossible without some demolition, if you know physics. Additionally the destruction had enough energy to dustify a lot of material and expel large fragments sideways.
2) The destruction covered up trillions of money and billions of illegal trades. It also killed the people that knew about the frauds. And even gold was likely stolen.
3) There were traces of thermite found in the dust, including vaporized steel (small spheres of iron) and molten Molybdenum.
4) The corrosive power of the dust was so large that it damaged cars, some surrounding buildings, and let the pile burning weeks afterwards under water.
5) The IDs of the remains of the crashed planes do NOT correspond with the IDs of the planes that were suspect. Instead they are IDs of military versions. Which happened to fly at the same time. 6) The heat was so extreme and explosions so large that fire-men could only be identified with DNA of remains (some was on other buildings). No passengers were found. 7) Transponders were switched off and switched on again, outside normal radar-range. This happened while military planes were at the same location. Almost everything is fishy with the planes. 8) Hijacking "exercises" were active at the same time, and military were active (even flying around), but all air-defence was down. 9) No plane fell in an empty hole, but was reported as such.

Extremely suspect and criminal behaviour
1) The owners of targeted departments had a company that produced micro-thermite.
2) The administration of the pentagon and of the CIA were both targetted, and "lost" trace of a lot of money. 3) Dancing israelis who were there before it happened and filmed the crashes. Their van had 2 towers and plane painted on them. And israeli art-group with fuse-cables. Mossad likely implicated. They are so in the open, that I believe, that it is also a distraction. 4) A lot of people with foreknowledge. One even appeared on a live TV show to "explain" what happened. 5) Completely intact passports of alleged hijackers were "found". Some of the alleged hijackers were still alive. 6) A lot of evidence was immediately destroyed. Flight-control information, destroyed material of buildings, etc.
7) Pentagon had no air-defence.. and no security cameras... 8) Many groups of people were working that year on the towers. They had time enough to prepare the demolition. But none of these groups can be traced back exactly.
9) The commission was controlled and led by implicated people. No investigation took place.
10) Important people in the government were likely involved, their companies were likely involved. And many in power made completely wrong decisions. Specialists were send away. 11) Laws were accepted and wars were started, which were all planned years before.