Defense or protection against external threats or attacks; can refer to systems or actions to safeguard a country or person (noun/suru).
政府は防衛力の強化を発表した。
The government announced a strengthening of defense capabilities.
自己防衛のための基本的な技術を学んだ。
I learned basic techniques for self-defense.
サイバー防衛は現代の重要な課題だ。
Cyber defense is an important issue in the modern era.