John Oliver's focus last night was how the national debt works, how valid concerns about it are, and how we should think about it for the future. (Spoiler: Unless you just started following politics, you already know the national debt only matters when there's a Democrat in the White House.) Via Yahoo News:

Importantly, "going into debt can actually be a good investment for the country," Oliver said. "Essentially, as economists will tell you, the key question is: Are you spending money on the right things?" Republicans "seem outraged" that the debt his growing, but only when Democrats are president — as some readily admit, he demonstrated, "but even if you put all of that bad-faith hypocrisy aside, we are still left with the key question: How much debt is too much? And the interesting answer to that is, nobody really knows."

The persistent low interest rates amid record high borrowing last year, among other things, "has made many economists start changing the way that they think about debt, thinking that — very basically — so long as our economy grows at a rate greater than the interest that we're paying on our debt, we can come out ahead," Oliver said. "There is a good-faith debate to be had about how to handle our national debt over the long term. But right now, most economists actually agree that with interest rates at historic lows, the question shouldn't really be 'How much debt are we taking on?' as much as: What is the value of what we are getting for it in return?"

"Look, no one credible is saying that deficits don't matter or that we should borrow as if the sky is the limit," Oliver said. "What they are saying is the debate shouldn't be about whether debt is good or bad, it should be about whether the investments that we are making are worth it or not. And if you are still worried about debt because you've been told that you are burdening your children and children's children's future, well I actually have some good news for you" — and a PSA from children that, like the rest of Oliver's explainer, has some NSFW language.

Go watch it. It will give you some good talking points the next time you get into an argument with your wingnut brother-in-law!