If there really were "a war to end all wars", would civilization stagnate?

WW I was seen as the “war to end all wars”, which obviously turned out to be a false hope.

But if there were a true “war to end all wars”, does it follow that civilization would ultimately stagnate and die?

- Wars encourage scientific, medical, and military research and development, thereby improving society through advancements in all of those area.

- Wars, at some level, contribute to population control, and as a side effect, reduced resource demand and lesser use of fuel, which in turn helps slow climate change.

- Wars (and deaths in wars) tend to cull out the violent people, thereby making civilization kinder.

Now, I’m not suggesting that we go to war just to achieve these goals. But if there were no war, would our science, technology, and medical research have been as successful and productive?