Because I am a bit fed up with hearing them:
It's all because we invaded Iraq
Not really. There was 9/11 and many British citizens, as well as those in many other countries were killed
If we pull out of Iraq and stop being pally with Israel and the US, the terrorist outrages will cease!
I think we all want them to cease right here and now (unless you are pro Al Qaeda or someone so ideologically bent that you have no moral scruples). But we are also attacked because we are seen as part of the "Decadent West". Such a comment assumes we are dealing with reasonable people. There is nothing reasonable about plotting to send a human detonator into a civilian or millitary area with the aim of that person blowing themselves up and causing maximum damage to human life and property
Iran and Al Qaeda are linked
Are they? I got the impression that they weren't bosom buddies, although I hasten to add that some evidence points the other way. But that said, neither were the USSR and China were friends during the 1960's, but both were individual causes for concern.
All these security checks at Heathrow and other airports are against our human rights
True they are not ideal, or helpful. But everyone is trying their best to help passengers. But hey, if you want it to stop and get blown up over the Atlantic...
It's all America's fault
The US Govts.. foreign policy has a lot to be desired sometimes, but nothing, absolutely nothing, justifies what happened on 9/11. Nor does kidnapping US citizens in Iraq and executing them on video, nor any other terrorist outrage. Some people are always prepared to believe the worst about the US (and they are not perfect as a nation), and yet these same people seem to be wilfully blind to similar abuses committed by nations that don't even have any form of democratic government! There is a word for that and it's called hypocricy.