Tony Blair responded to 7/7 by rushing out a twelve-point plan which his Home Secretary hadn't had proper sight of, and which the Labour Chairman of the Home Affairs Select committee called "half-baked". Much of it was never implemented, which was just as well, and its most startling feature was immediately dropped – new powers to close mosques (as if that would have helped). One of its main proposals was to hold suspects without charge for up to 90 days. This was red top government: the then Prime Minister was running the country as if he were a tabloid editor.
David Cameron responded to the murder of Lee Rigby by saying that he is "not in favour of knee-jerk responses. The police have responded with heightened security and activity – and that is right. But one of the best ways of defeating terrorism is to go about our normal lives." He also confirmed that the Independent Police Complaints Commission and the Intelligence and Security Committee will examine why the suspects weren't fully investigated – despite being known to the police and security services. (The independent coroner's inquiry into 7/7 didn't open until 2010.) This style of government was presumably what Cameron meant – though he cannot have foreseen the terrible circumstances – when he said in opposition that politics shouldn't be a branch of the entertainment industry.
The Prime Minister brings sense and restraint to difficult statements. Imagine how Blair would have milked the Bloody Sunday statement in the Commons, or the statement on the Hillsborough deaths – or how he would have tried to stampede half-baked legislation through the Commons after the Cumbria shootings. During the last few weeks, I've compared Cameron to John Major, which wasn't a compliment, and mentioned him in the same breath as Lord North, which wasn't one either. But criticism where it's merited should be balanced by praise when it's deserved.