The desire for more advanced weapons during World War I inspired significant investments in scientific research and applied engineering in both Germany and allied countries. World War II spawned even more widespread scientific research and engineering development in such fields as nuclear chemistry and nuclear physics as scientists raced to contribute to the development of radar, the proximity fuse, and the atomic bomb. In Germany, scientists such as Werner Heisenberg were being pushed by the leaders of the German war effort, including Adolf Hitler to evaluate the feasibility of developing atomic weapons in time for them to have an effect on the outcome of the war.