Republicans lost the Congress in 2006 and 2008 as a result of their own corruption and arrogance, as you pointed out. But that does not mean that the Democrats will lose the house or senate for committing the same sins. There is virtually nothing, no leftward lurch, the Democrats could do which would result in them losing black districts. That is also true for our metropolitan centers such as New York, San Francisco, Chicago and Los Angeles. Since these metropolitan centers dominate the state, the Senate in many states is virtually impervious. There is no reciprocity across the board for Democrats who overreach. Many of them, like Ted Kennedy, are virtually immune.
So the Democrats can lose a lot of seats and perhaps even for a time control the House or Senate but the overall trend is not to be altered by finding better policies or more charismatic candidates.
It is always risky to assert that "this time it is different" but sometimes, for example in America in the 1850s if you were warning the Whigs, it would be right to say, "this time it is different." This is precisely what James Carville and the authors of the piece are asserting because of the demographics. I agree with them. That is why issues alone are unlikely-although not impossible-to restore Republicans, even temporarily, to power.
It is also necessary to understand that, although in our lifetime though no political party has died, the Dixiecrat wing of the Democratic Party which was staunchly opposed to integration was absolutely killed off and died in the 1960s/70s. So the Democrat party survived but the entire southern section of the party as it was then constituted simply disappeared. It is likely that we are experiencing the same fate for the conservative philosophy in the northeastern section of the Republican Party. Sure, the Republican Party will endure, the name at least will endure, but what of the animating party philosophy?
In the case of the northeastern Republican Party today, its existence is threatened not for the want of persuasive and sound political philosophy, as was the case with the Dixiecrat's, but by the irresistible glacier like movements of population.
