No, it is not entirely, or even primarily about political cowardice. It is instead about the nature of the two parties. The democrats are the party of trying to get things done and social justice. The republicans are the party of big business and avoiding change. In order for the democrats platform to pass, they need an affirmative vote in Congress for appropriations or regulations, and with the exception of war spending, it is very difficult to get that. All republicans ever have to do is say no. That fits in with their ideology perfectly. Throw in a few conservative democrats from red states, a media that is very much bought or terrified of being called liberal, corporate lobbyists throwing money around like candy, a friendly Supreme Court, and even a disorganized base, and it is no wonder that democrats can do almost nothing, even when they had a significant majority in Congress just a year ago. That's also the reason that republicans can get almost all of what they want even though they hold just the House.
There are two small glimmers of hope in all of this, though they each have major downside for the time being. First, the demographics of the republicans are against them. The strongest part of their base is composed of older, white conservatives. They are not only baby boomers, but the silent generation which is now almost entirely in their 70s and 80s. This is not a demographic that provides for long term stability. Throw in the outright hostility exhibited towards minorities, gays, women, and younger Americans, and there really is not much chance that the republicans will pick up much support from those groups in the coming years.
Second, a lot of people noticed what was going on the last few months in Congress, including the media. Although it's too early to say what will happen with campaign support for republicans and tea partiers over the next few years, it is very clear that outside groups that have an interest in our economy (namely the rest of the world and a lot of business leaders) will start making some noise about how this whole fiasco was handled, particularly if this happens again in a few months on the budget or some other major issue. We've already heard from China on this, and I wouldn't be surprised if we hear from other developed nations in the near future. We may even see a move away from the dollar as the reserve currency, and a downgrade of our credit rating is a very strong possibility.
No matter what, the rest of this decade is likely going to suck hard. Too many policies are in place that will be very bad for a lot of people, especially those in their 50s. And if the dollar does become just another currency, rather than the most desired, that will ripple throughout our economy in ways we probably can't even imagine right now. But even the republican cannot hold back mortality or avoid global economic reality forever.