War prompts governmental investment and research of/into fields that would otherwise remain on the backburner. As you accurately mentioned, that creates competition.
Humans as a species has evolved to be inactive, only creating enough to sustain themselves, unless prompted into activity. War and any activity in general where there must be a winner and loser creates that prompt. Encryption, for example, would not have been even considered if there was no need to pass messages in a safe manner.