How is isolation the most effective policy

From my point of view it is not so effective since it is like living in a neighborhood and not talking to the neighbors. You can live like that but it would be hard. Countries need other countries in today's interconnected world. In the past it proved to be a bad approach. For example, Roosvelt refused to declare war against Germany and was obliged to declare war to Japan after the susprise attack to Pearl Harbor in 1941.

answer; i believe its a

world war i began in 1914, after the assassination of archduke franz ferdinand, and lasted until 1918. during the conflict, germany, austria-hungary, bulgaria and the ottoman empire (the central powers) fought against great britain, france, russia, italy, romania, japan and the united states (the allied powers). to new military technologies and the horrors of trench warfare, world war i saw unprecedented levels of carnage and destruction. by the time the war was over and the allied powers claimed victory, more than 16 million people—soldiers and civilians alike—were dead.

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