Finding terrorists who haven’t yet struck is like looking for a needle in a haystack. In fact, it may be looking for needles where there aren’t any. Ars Technica put up an interesting but deeply concerning piece yesterday regarding the use of the NSA’s SKYNET program to automatically identify terrorists based on metadata. Patrick Ball—a data scientist and the executive director at the [Human Rights Data Analysis Group](https://hrdag.org/)—who has previously given expert testimony before war crimes tribunals, described the NSA's methods as "

All this week I have been writing about issues of health in the United States. Americans are less healthy than our counterparts in other wealthy countries, for a variety of reasons. But the two biggest reasons are poverty and culture. Poverty can be dealt with using the bluntest of methods: throw money at it. It works. Food stamps, welfare payments, and other programs have been effective at poverty reduction, despite the bad press they have received and constant harping by conservatives that such initiatives only create generations of government dependence.

The series is not done yet! Today, I am writing about issues of American health and the ways in which they are bound up and influenced by morality politics. There’s no point mincing words: American attitudes, by and large, are more conservative than those of citizens in other wealthy countries. We are more religious, we take religion more seriously, and part of that is assigning moral components to almost every public policy decision.

Continuing on the theme of issues in American health, this time I want to talk about two things that haven’t gotten much attention so far: mental health and addiction. The good news is that mental health in the United States isn’t as stigmatized as it used to be. Overall, we speak about it more openly, and are more willing to seek treatment than in the past. The stigma is eroding, albeit slowly.

Given the title of yesterday’s article, it should be clear that this one is intended as a sequel, hitting on similar themes, but focusing more specifically on black Americans, who I believe didn’t get much focus in the study discussed yesterday. First things first: black Americans have lower life expectancy than white Americans. This is well borne out by statistics. The most straightforward way to put it is that black men and women today have the same life expectancy as their white counterparts did in 1970.

Recently, Democratic Presidential candidate Bernie Sanders released his healthcare reform plan. Suffice it to say, it’s a single-payer system. Others say this is unrealistic, impossible, etc. Many Americans are frustrated by the reality of the Affordable Care Act, when compared to what was promised. (This is ignoring, for the sake of argument, those who hated it all along.) If we could magically have a single-payer system tomorrow, would it work? Would it be cheaper?

Confession: I hate driving. Some people enjoy it. I don’t. I never have. I don’t get the fascination. So, when it comes to self-driving cars, I may be a little (OK, a lot) biased. I want them yesterday, dammit. But I’ll try to be fair here. What’s good and bad about them? Over the past several years, we have seen self-driving cars go from science fiction to being well within reach.

In a political culture divided not simply by ideology, but basic judgments about reality, it should be no wonder that echo chambers–homogeneous clusters, in the research parlance–are commonplace. A couple of papers were brought to my attention, both written by (more or less) the same group of Italian researchers. They are: * [Debunking in a World of Tribes](http://arxiv.org/pdf/1510.04267v1.pdf) * [The spreading of misinformation online](http://www.pnas.org/content/113/3/554.full.pdf) I will quote from both, as needed.

Constructivism, like most philosophical ideas, sounds complex and intimidating if you’ve never heard it before, or are unfamiliar with what it means. But it’s actually not that complicated. I was doing some thinking about it earlier today, and thought of a rather straightforward way to explain it. Take something that’s a simple physical fact–such as the temperature of water. Temperature is essentially how energetic the molecules of water are: if they’re more energetic, they move faster and are hotter; if they are less energetic, they move more slowly and are colder.

The 21st Climate Conference, also known as COP21, was just held in Paris. It is the most important international climate change agreement made at least since 1997’s Kyoto Protocol. But is it good news, or bad? Among environmentalists, there is disagreement as to whether the accord coming out of Paris represents a positive outcome: The major mainstream U.S. green groups are singing the Paris Agreement’s praises. Take the Sierra Club. “President Obama’s leadership in getting the world to this landmark agreement, a turning point for humanity, will go down in the annals of history,” said Sierra Club Executive Director Michael Brune.