In Southeast Asia, the United States government used the domino theory to justify its support of a non-communist regime in South Vietnam against the communist government of North Vietnam, and ultimately its increasing involvement in the long-running Vietnam War (1954-75).
The number of voting representatives in the House is fixed by law at no more than 435, proportionally representing the population of the 50 states.
House of Representatives or simply House is the lower house in US polity and at present consists of 435 members with different numbers coming from different states. The number of Congressmen from a state is dependent upon the principle of proportional representation.