I'm pretty wound up about the responses in this thread, so I'm going to come across a little hot, but it is not directed at you. You are asking a very important question, and you deserve a decent attempt at an answer.

First things first: everyone telling you to run away and do nothing is wrong. It's fine to limit your exposure to the World Wide Skinner Box and all, especially if it is eating all your free time, but disconnecting entirely is not the answer.

The word "idiot" comes to us from ancient Greece. “Idiotes” (ΙΔΙΩΤΕΣ) was a word used to describe people who abdicated their civic duties and stayed entirely absorbed in their own lives. Yes, it was meant as an insult. It still is, but it used to, too.

Your problem is that you aren't an idiot.

The best thing you can do is go out and act on these feelings. Getting stuck in a loop of "Read, refresh, despair" absolutely sucks. It makes a person feel so helpless. It's the worst.

The trick is to realize that you aren't actually helpless. Sure, you can't personally convince everyone in your country that maybe they shouldn't (for example) throw away democracy, nor can you expect to solve world hunger all alone. The biggest problems can't be solved all in one go by an individual. This can be hard to admit, especially for we folks who grew up reading sci-fi competency porn, but the first step to feeling better about your place in the world is to be honest about what you can do from a standing start. You're only human, and that's OK.

But still, you can act, and in a big way. How? What you CAN do is apply the same skills you use in programming to the big problems, i.e. break down the problem of your choice into smaller pieces that you CAN realistically attack. Then, pick a promising problem fragment and budget time, say 3-5 hours a week to start with. Don't try to do too much, especially at first, lest it become a huge burden that you resent. You still need to have time for fun stuff like visiting friends and wrecking noobs on your favorite war-themed hat simulator.

The easiest way to do this (in my personal experience) is to find a local cause to attach yourself to. You can absolutely make a huge difference in your local space. Bonus points if you can use your particular skill set to help, that's a substantial multiplier!

Does a local charity you like run their entire operation off of a 12 year old Dell Opteron running Windows Vista? BOOM, you can help!

Local political campaigns are just getting started, and getting in now will give your opinions more weight inside the campaign organizations since you'll be getting in on the ground floor. Does a local candidate need help managing their data operations via VANS/whatever the Republicans use? Could you run for something? BOOM, there you go!

Hell, it may be enough to find a meetup of people who drink (beer or coffee) and worry about the same things you do. History has loads of examples of great stuff that has come from sharp people hanging out in bars and cafes and shooting the shit (Bar napkins can be used for way more than physics problems!). Plus, you might get some new friends, which is also great for pulling yourself out of the aforementioned dark places all on its own.

If your experience matches mine, you'll feel loads better having put your shoulder to the burden and pushed. You won't be a bystander anymore. Agency is a currency that feels like solid gold, my friend. It won't make things not suck, not immediately, but you'll be doing your part, and that'll go a long way.