To make biofuels part of the solution instead of part of the problem, we need a carbon tax.

Raising the minimum age for buying guns would not do much to prevent killings in schools.

Banning high-powered rifles like the AR-15 is useful because the wounds they cause are especially likely to be fatal.

Eliminating the loopholes in the background check system would prevent some killers from getting guns.

The Canadian system of gun control works pretty well; we could copy that.

If We Want to Support Refugees, We Need To End the Wars That Create Them.

The chemical attack on Sergei and Yulia Skripal was carried out with an unusual nerve gas developed in the Soviet Union in the 1970s.

Since the chemical structure is a secret, not many groups could have made it.

This is not yet conclusive proof that Russia carried out the attack, but does make it likely.

Being realistic about nuclear weapons means recognizing that complex systems do not always work as intended.

Indeed, a complex system often has failure modes that nobody anticipated, not even the designers, and that the people operating the system were therefore never trained to deal with.