How many letters does the top answer for “a war measure that isolates some area of importance to the enemy” have?

The most common answer is blockade (8 letters).

Crossword clue: a war measure that isolates some area of importance to the enemy

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

blockade 8 letters wn-def

a war measure that isolates some area of importance to the enemy

encirclement 12 letters wn-def

a war measure that isolates some area of importance to the enemy