How was the truman doctrine a change in previous us foreign policy? question 1 options: the truman doctrine encouraged the us to withdraw itself from world affairs and let countries sort out their own differences the truman doctrine aimed to decrease military spending and increase the national surplus the truman doctrine was a shift from isolationist policy because the belief that it was the us’ responsibility to stop the spread of communism to weaker countries around the world the truman doctrine encouraged the us to “speak softly and carry a big stick”