The average speed of rail freight on this route, because of hold-ups at frontiers, customs inspections and the like, is barely 9mph.

ECONOMIST: A better way to fly

Even if American freight carriers were to copy El Al, Israel's airline, and hold goods for a day for security checks, it would not greatly erode the advantages of air freight over other means of transport.

ECONOMIST: Can it ever again be business as usual?

That has blurred the line between express services and air freight, and led to increasing use by integrators of spare hold capacity on passenger planes.

ECONOMIST: Global express-package companies