the Berlin Blockade convinced Truman that the west
was at threat from Stalin and NATO was made to deter
the USSR or its satellite states from attacking any
western nation
as a military alliance all 12 members of NATO agreed an attack on
one was an attack on all meaning the USA would also use it
military to help its members such as GB and France
Europe was already divide by economic differences and
alliances and now it was divided into military alliances
Stalin saw this as an aggressive act so straining relations more
NATO served its purpose and prevented a war in Europe
its debatable how much of a threat Stalin was but NATO
mean that any military action would risk nuclear war with
the USA