What new techniques and technologies were developed to keep warships safer during combat on the high seas?​

For the U.S. it implimented the technique of keeping boats and ships sailing in groups as to make it harder to attack.

answer: wait what

explanation:

lend lease program was passed by congress on march 11, 1941. the president could ship weapons, food, or stuff to any country whose struggle against the axis assisted u.s. defense