Lady Jean, that is an assumption. It's quite possible that you are correct, but your assumption is not proof of anything. The only way to know for sure is to investigate.

There was a lot of work being done on the WTC during the weeks leading up to 9/11, and there were a lot of workers accessing the parts of the building were people would need to go if they were going to plant charges. There was a maintenance space in between each floor where people could move about and do whatever they needed to do without the tenants of the buildings being aware of them. And the Bush family was closely tied to the company that had the security contract on the buildings of the WTC. So we really can't say with any certainty that there wasn't sufficient opportunity for someone to plant charges in the buildings. The only way to know for sure is to conduct a thorough, scientific investigation, and a rigorous peer review of the results.