How did modern weaponry contribute to both the sinking of the lusitania and the bombing of london?

Submarines and airplanes--these new technologies changed warfare and contributed to more intense naval and air battles. 

Submarines or U-boats (German) were able to attack ships without warning and without ships knowing they were there. Germany used submarines and missiles to attack ships both military and merchant. 

Airplanes were used to release bombs on cities. The weaponization of airplanes was new and not able to defend against the air attacks. The bombing of London was a morale hit and massive attack against civilians using bombs from airplanes.