Answer:
The need to have the Jet Engine developed became very important because several countries wanted to acquire and gain more advantage over others during war.
Step-by-step explanation:
One of the earliest examples is that of the Ottoman Army.
Ottoman Lagari Hasan Çelebi in 1633 for instance gained a position in the Ottoman army because he was able to develop and successfully test a cone-shaped rocket.
The second example would be that of the German Ministry of Aviation. This ministry was responsible for the production of all Aircraft in Germany whether it as for military or for private purposes. Their priority, of course, was the development of air transport for military purposes.
So it's wonder when in 1933 they gave support to Engineer Paul Schmidt for pioneering a pulse jet engine that was more efficient than that of Robert Goddard.
Also, just after the above, in 1943, the Heinkel-Hirth 109-011 was developed with the singular purpose of advancing the war efforts of Germany.
After the war, German jet aircraft and jet engines became a guide and a model for those developed in Soviet Union and the United States of America.