Posion Gas
No, definitely not Poison Gas. Radar as such is not a weapon, but it was decisive in the Battle of Britain, same applied to Asdic in the Battle of the Atlantic..... The Merlin engine as made by Rolls Royce is not a weapon, but it made the Mustang one of the best aircraft of all time. I'm thinking the answer is the 17 pounder A/T gun mounted on a Sherman chassis, the Sherman Firefly.... The Spitfire.... The Mosquito.... The Lancaster...
the tank
The use of chemical weapons during the first World War ; see relevant link below .
Britain had a coalition government during World War 2
The atomic bomb was the first nuclear weapon ever made during World war two and it was the first weapon that have been tested before Hiroshima was under attack.
Britain wasn't invaded during World War 2
The nuclear bomb.
Nuclear weapons
Nuclear weapons
Nuclear weapons
Nuclear weapons
It should be the bayonet
ya mum