But that does not mean that more effective checks on the mentally unstable are impossible, or that restrictions on the killing power of what can be sold are doomed to failure.

The US can expect to be the sole superpower for some time yet, if we mean by the term a state capable of deploying effective power almost anywhere in the world.

The effective shear stress not only generalizes the flow intensity but also summarizes the flow intensities of mean flow velocity, stream power and unit stream power.