How did new technologies change the nature of war in World War I? How did new technologies contribute to the large human toll and the long stalemate?
How did new technologies change people's perspectives about war?

The new technology made the war bloodier and bloodier year on year, and showed the generals that this was a new kind of mechanised warfare, unlike any other war that came before. The technology was deadly such as the machine gun, which caused the stalemate as no side could push through such unforgiving rapid fire with sufficient survivors. All this also changed people’s perspective on war, it was no longer romanticised, and people understood the bloody, cruel, horrific nature of mechanised warfare, and the destruction that it brings.

The answer is professionals such as attorneys.