The image of a special-forces helicopter landing on London Bridge on Saturday night raised the question of whether the British capital is becoming more dangerous — or is in fact better defended than ever.

The attack, which killed seven people, was the second time in three months that London has come under attack after a similar assault on the country's Parliament in March. Prime Minister Theresa May was accused on Sunday evening by Labour Party leader Jeremy Corbyn of failing to protect the public by starving the police of funds.

And yet, the three terrorists who carried out the London Bridge attack were dead within eight minutes of the incident starting after police officers — who are generally unarmed in the U.K. — fired 50 rounds. Four years ago, it took 15 minutes for police to arrive on the scene when an off-duty soldier was attacked by two Islamic extremists. Even then, they shot to wound — rather than kill — the assailants.