The chief problem of American political life for a long time has been how to make the two Congressional parties more national and international. The argument that the two parties should represent opposed ideals and policies, one, perhaps, of the Right and the other of the Left, is a foolish idea acceptable only to doctrinaire and academic thinkers.
Instead, the two parties should be almost identical, so that the American people can “throw the rascals out” at any election without leading to any profound or extensive shifts in policy.
The policies that are vital and necessary for America are no longer subjects of significant disagreement, but are disputable only in details of procedure, priority, or method: we must remain strong, continue to function as a great world Power in cooperation with other Powers, avoid high-level war, keep the economy moving without significant slump, help other countries do the same, provide the basic social necessities tor all our citizens, open up opportunities for social shifts for those willing to work to achieve them, and defend the basic Western outlook of diversity, pluralism, cooperation, and the rest of it, as already described.
These things any national American party hoping to win a presidential election must accept. But either party in office becomes in time corrupt, tired, unenterprising, and vigorless. Then it should be possible to replace it, every four years if necessary, by the other party, which will be none of these things but will still pursue, with new vigor, approximately the same basic policies.
— Tragedy and Hope: A History of the World in Our Time by Carroll Quigley