Cameron appears to be advocating the greater use of intelligence in the military and the political/strategic sense, but he is unrealistic if he believes warfare can be made any nicer. Aggressive acts by enemies require firm response. Israel has learned that, and by giving a firm response to attacks, has achieved some progress.
Far from criticising, Cameron should be learning.
Likewise the USA has tightened up her immigration procedures and giving of visas in the last five years and taken control of her borders, while in Britain, we’ve allowed the EU to swamp our country with uncontrolled immigration, and Human Rights Acts have provided fomenters of hatred full rein.
Given that we don’t control our own country, we have little choice but to play gently, but we would be wrong to criticise others who have taken control, reacted strongly and successfully to terrorism.