Will religion lead to the end of mankind?

That is interesting. I have never really gone into it that far. From what I know the cons made their first major gains during the power vacuum that afflicted the republican administrations at the end of the water-gate era. They then as you say reached full flowing during the Bush Cheney years only to suffer significant reverses on the military and political battlefield.

Historically it can be argued that the the political, economic and social/ethnic pluralities that segment US society acted as a brake on domestic statist projects. Many on the left like G, Kolko argue that these same factors helped prevented the formation of a significant socialist or social democratic party in the US inhibiting the formation of a more inclusive polity a least for progressives. However whether these factors will be enough to slow the inexorable growth of the national security state is another issue. Hanna Arendt once warned us against the dangers of state and non state actors using the tools and capabilities that have been gained through external empire building and the unsavory practices that these activities commonly engender and turning them against their own domestic national populations.

Naturally invoking external and internal enemies has been and continues to be a useful tool for political operatives to bully domestic opponents and expand a regimes power and reach over the lives of its citizens. But I suppose many would argue that it can be a good thing on occasion the success of the writer and political pamphleteer Thomas Paine attests to its effectiveness in the east coast colonies at the beginning of things in your republic.