It's a shame she didn't feel compelled to resign when she was found guilty of breaching the ministerial code. She's a mildly controversial figure, and while I applaud a person acting on their convictions there a numerous examples in the past where it would have been even more apt for her to stand down, but she never did.
In any case, I believe she is wrong. The Foreign Office has played a huge role in negotiating a ceasefire. Were the UK government to go about gobbing off and getting people's backs up then that reduces any influence we can bring to bear on events. In light of today's ceasefire and the revelation of the part our own Foreign Secretary and diplomatic service had in bringing it about it was right and proper that Cameron politely declined to outright condemn the Israelis when asked to to so the other day.
To cap or all off, her resignation letter was quite scathing, slagging off various ministers for their uselessness, including our new Foreign Secretary, the very day our new Foreign Secretary announced the ceasefire to the British public.
Not only was she a day late but hindsight has almost immediately proven her wrong. Just because she didn't know what was happening, it doesn't mean there was nothing happening. A beautiful piece of bad timing on her part.