Einstein primarily emigrated to the United States because he had a Jewish background, and Adolf Hitler, who became Germany's chancellor in 1932, was about to adopt Anti-Semitic policies.
It was a very hard choice for Einstein to choose to emigrate to the United States, but it was a very wise one. As a Jew, he knew what was gonna happen if he stayed in the United States. You may already know that the Holocaust happened a few years later, in which most Jews living in countries occupied by Germany were murdered. Thanks to moving to the U.S, Einstein was safe from this event.
<span>B) Pre-war alliances were made in secret and elevated diplomatic tensions within those governments.
Or sometimes the fact that alliances were being made was announced publicly -- but the negotiations about the alliances were conducted behind closed doors. And often the terms of the alliances were kept secret, so that only the parties involved knew the full details. This contributed to an attitude of escalating nervousness and tension as the nations of Europe maneuvered for strength over against their perceived adversaries.
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