Quote: headhunter "... it is a little disingenuous to say he was 'attacking Parliament' when he was attacking complete strangers outside.'"
It might be, if your personal definition of "disingenuous" is not the one we get in dictionaries, but something else you just made up.
You don't have to agonise over detailed analysis of everything he did, though. Just the bit where he entered the grounds of Parliament and knifed to death a policeman trying to stop him getting into the building. That bit. And had to be shot to halt his determined attempt. It is reasonably fair to say he was making a direct attack on Parliament when he was, er, making a direct attack on Parliament.