It's Check and Balance....same thing applies to the cycle of American Politics. The cycle of these two parties is what makes America as America.
Republican-War and downward spiral of economy. The gas price might not be cheap as of right now, but they've secured a phenomenal future over its access in the Middle East, the 2nd largest. It'll ripe in the future.
Democratic-No War, economy picks up, gas is cheaper, but the security of America is weak. Then Republican step in after them and the cycle repeats.
Way to go Nancy Pelosi....women can do something drastic, maybe it's time for Hillary to be the next president?