When prominent scientists - with a reputation to lose - publish things like this.
It is particularly worth following the links from his piece (although the links to the videos at 911research.com appear to be broken)
I have to say I am now convinced - finally - that the "official" version which has the buildings falling as a result of intense fires is dramatically less credible than the controlled explosion hypothesis. It always was remarkable how neatly the towers collapsed almost within their own footprint but I wanted to believe the official versions. At least initially.
Why did I want to believe?
Because it was bad enough having to come to terms with the implications that the world now contains a bunch of Terrorists so "committed" that they are prepared to kill themselves in order to kill thousands of innocent civilians. Having to add to that the implications that they were aided and abetted by the people who we thought were supposed to be protecting us raises the stakes beyond anything in previous human experience.
As you may have read in the previous post, my chief reason for rejecting the main 9-11 conspiracy theories is that, if true, they indicate a level of intelligence, foresight and planning which has been so markedly absent ever since that it is impossible to imagine that the people who planned 9-11 (if we are to accept the conspiracy theories) are the same people who have conducted the war on terror and the ongoing imposition of the Police State of America.
I still have that problem. I am now 95% convinced that explosives were preplanted in all three WTC buildings. This clearly implies at least detailed foreknowledge of the attacks and, at most, the planning and implementation of the attacks. Furthermore, the range of people who would have undisturbed access to all three buildings to the extent of being able to plant several tons of high explosive is extremely narrow. It is inconceivable that foreign terrorists are on that short list.
A tentative picture is forming. The fundamental plan was indeed down to MIFT. However, Mossad got to know about it and informed the US Government. Between them they decided to exploit the opportunity such an attack would present. This involved Mossad being granted access to plant the explosives (leaving plausible deniability for the US Government) and Cheney to organise the essential distracting drills which took place while the attacks were going on and allowed Cheney to pull the defensive fighters away from the attacking planes.
If that outline is remotely close to the truth, then not only have we witnessed one of the most outrageous criminal mass murders in human history but we have to face the fact that we live in a much more dangerous world than even I have, up to now, imagined.