That goes for the entirety of this lightweight government!
There are 650 odd MPs and I remember listening to PMQs with Maggie Thatcher. She was briefed and prepared for questions on any issues which might arise from any of them.
Compare that to Tony Bliar: I have lost count of the number of times I have heard him (& GB come to that)say the words : "I wasn't aware of that but will investigate and get back to you"
On the subject of not being on top of their brief the Defence Secretary and Armed Forces Minister come immediately to mind. I expect they can sleep at night only because they are blissfully ignorant of how hopeless they really are.