That brings up a good point, I can read entire books and I often listen to music for hours on end. I want to be informed on politics and world news, but I guess that I don't like reading about them haha.Can you read an entire article on something you enjoy learning about? If so, you have the attention span -- you just need to work on translating it to subjects that don't immediately grab you.
I'm jumping to conclusions a bit, but it sounds more like you feel you should be more informed on politics and world news, as if there's an expectation on you to be, rather than actually wanting to be. It makes all the difference. You can listen to music for hours on end and read entire books because you want to. If you felt you should do it because of some outside expectation I bet you wouldn't be able to spend half as much time on them. You just can't feign interest in things. You're going to have to become invested in things to gain genuine interest in them. Do some background research, spark up conversation with people on the subjects, set a specified time aside to do whatever it is. But at the end of the day, if you don't have any empathy towards something or an interest in a particular area there's no point torturing yourself trying to become involved in it.
I've been following news websites and blog-ish type places (like reddit) for about 2 years now. I feel invested in political subjects, but I only ever read headlines or watched videos. A few months ago I decided that just reading sensationalist headlines wasn't giving me a proper view of things, so I vowed to start reading entire articles. My main issue is that I'm just so bored doing so. The articles are usually summed up nicely by the title anyways.