he made 480 mil on wtc7 alone.
he put down $14 million down payment on the towers, six weeks before 911.
911 hit, and he has cashed insurance for 7+ Billion.
Hell of an investment.
Also, in spring 2002, NYC was going to shut down the towers because the asbestos hadn't been removed. They were going to close the doors. It would have been a financial backbreaker. Silverstein bought them anyways. And, he didn't even start the asbestos process (which would have taken a year - the towers would have been shut down for some time in the spring even if he had started the One Billion Dollar asbestos removal project immediately.
You wanna talk motive? He turned 14 mil into 7 billion. He bought a doomed project and didn't bother fixing it. Instead, he just "pulled" it.
Look at Silverstein more. Look at the asbestos issue more. Hell, look at the corrosion studies - many thought the towers were going to have to be demolished anyway.
Motive, motive, motive. Problem is, if you are going to commit insurance fraud, you shouldn't do it with 3000 people in the buildings.