Someone who's hawkish is in favor of going to war with other countries. The president's hawkish advisors will frequently recommend military solutions to conflicts.
In politics, the adjective hawkish is useful for describing people, groups, or political parties that consistently prefer the war option for reacting to problems around the world. A hawkish politician, also called a hawk or war hawk, might vote in favor of continuing a military operation instead of ending it, for example. This word dates from the 1960s.