Let's take a more global perspective on this. The US may be in the center of the media attention, but it comprises less than 6% of the world population and its share of the world production is shrinking. So the struggle is going on, alright, but elsewhere - and will be won (I hope) elsewhere. But it will not happen here. The US already had its 15 minutes of fame, and now is sliding back to barbarism.
So if we were to take your suggestion of not giving up the hope - we should be true to the Left tradition of internationalism and universalism. That means embracing globalization rather than fighting it to protect the institutional status quo of the United States. We should write the United States off, abandon the US-centric thinking (whose Left version is "the US is singularly and exceptionally bad") and take a truly global perspective.
Wojtek