Why did the United States and the Soviet Union become involved in an arms race?

The US/USSR arms race was seeded in the use of Nuclear weapons against each other

Explanation:

The tension between the US and the USSR was something that had been building for years throughout WWI-Vietnam (even longer till 1991 and the dismantel of the Soviet Union). The use of the atomic bomb by the US in WWII    even after the alliance the two countries had, started the competition. There was an amount of distrust since the US didn't disclose their plans to drop the bomb on Japan, to the USSR.

After the end of WWII, the two powers were on opposite ends of their views on communisim. The USSR sought to expand their rule over Europe and the US was buliding their defences against that possiblity. Knowing the US had nuclear weapons, the Soivets tested their Atomic weapons in 1949, which was the true beginning of the Cold War. The US went on to test the Hydrogen Bomb, in 1952 and the USSR followed suit in 53. The arms race turned into the famous Space Race, which the USSR led by launching a satellite into space, pushing the US to put a man on the moon by the end of the 60s.

Major events:

The Bay of Pigs, 1961 which was an unsuccessful invaision of Cuban exiles backed by the US leading to tension between the US and Castro

The Cuban Missile Crisis in 1962, between John F. Kennedy, Fidel Castro and Nikita Khrushchev.

in 1803 the louisiana purchase took place, doubling the size of the country. by 1840 almost 7 million americans had migrated westward in hopes of securing land and being prosperous. the belief that settlers were destined to expand to the west is often referred to as manifest destiny.

explanation:

                the united states presidential election of 1912 was the 32nd quadrennial presidential election, held on tuesday, november 5, 1912. the election was a rare four-way contest.

                incumbent president william howard taft was renominated by the republican party with the support of its conservative wing. after former president theodore roosevelt failed to receive the republican nomination, he called his own convention and created the progressive party (nicknamed the "bull moose party"). it nominated roosevelt and ran candidates for other offices in major states. democrat woodrow wilson was finally nominated on the 46th ballot of a contentious convention, to the support of william jennings bryan, the three-time democratic presidential candidate who still had a large and loyal following in 1912. eugene v. debs, running for a fourth time, was the nominee of the socialist party of america.

                wilson won the election, gaining a large majority in the electoral college and winning 42% of the popular vote, while roosevelt won 27%, taft 23% and debs 6%. wilson became the only elected president from the democratic party between 1892 and 1932, and the second of only two democrats to be elected president between 1860 and 1932. this was the last election in which a candidate who was not a republican or democrat came second in either the popular vote or the electoral college, and the first election in which all 48 states of the contiguous united states participated.

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-austint1414