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The 25th Constitution's Amendment, act proposed by the Congress and ratified by the states in the aftermath of the assassination of the President John F. Kennedy. This amendment in the Constitution of the U.S. was added with the aim of putting itself in action for replacing the President or Vicepresident in case there is an avent of death, removal, resignation or incapacitation. In 1970s, the amendment started to act within these procedures.
The vicepresident John Tyler assumed the Presidency after the sudden death of the President William Henry Harrison, he was the first that reached that position without postulating for any election. These amenment was added with the necesity of feeling safe in case these type of situations happen again, to establish order within the nation of the U.S.