In my last blog earlier this month about the London bombings of 7 July 2005 there was a lot of concern expressed by people who say that when they question such events they're told they're "mad, crazy or in a state of shock". I haven't done this and won't.
What we will do is investigate an issue. For the new series we have looked for key proponents of alternative theories.
So for the new programme about World Trade Center Building 7 (The Conspiracy Files: 9/11 - The Third Tower for next Sunday) we have interviewed at length the architect Richard Gage, the former professor of physics Steven Jones and the writer of Loose Change Dylan Avery.
We have then taken their questions and arguments and tested them.
We've looked for new photographic and physical evidence, for key eyewitnesses and spoken to experts and investigators who have been involved in trying to understand what exactly happened to bring down Tower 7.
It does matter that a lot of people think the US Government is "hiding something" about 9/11. According to one American poll more than a third of those questioned thought government officials either assisted in the 9/11 attacks or allowed them to happen.
And it does matter that according to the official explanation Tower 7 was the first skyscraper to collapse because of fire. Smaller buildings have collapsed due to fire but never a 47-storey skyscraper.
The final official report on 9/11 by the National Institute of Standards and Technology is eagerly awaited not just by critics but also by those who want to know how safe skyscrapers are.
I'm happy to debate the issues. In next week's programme we will look at the what some people have said was the neat symmetrical collapse of Tower 7, we will look at the dust found around Ground Zero, we will look at the BBC's alleged involvement in a conspiracy, and many other issues.
But I've seen there's already a campaign for letters of complaint well before the programme has been aired.
Alex Jones' Prison Planet website ended an article headlined BBC Hit Piece by urging readers to comment on this blog. And comments in 911blogger.com urged people to prepare a "counter strike" and to start letter writing and e-mailing. A lot of the later comments on my last blog came soon after those.
It would be good if people watched the programme first. So far we've put out a three minute trailer:
In response to dotconnect: yes I'm interested in investigating a host of issues such as the death of Anna Politkovskaya, the financing of al-Qaeda, British agents in Northern Ireland - and it does not as you suggest hinge on whether "our side" was allegedly "behind it". But the BBC has already covered these stories and is currently investigating many of them.
In response to cyncastical: the original allegation made in the papers was that we had paid Nicholas Kollerstrom to appear in the programme about 7/7. We did not. We reimbursed him for £30 worth of his expenses. The newspapers corrected their original copy.
The Conspiracy Files: 9/11 - The Third Tower to be broadcast on BBC Two at 2100 BST on Sunday 6 July, repeated on BBC 2 at 1120 BST on Tuesday 8 July, and on Signzone at 0130 BST on Wednesday 9 July.