And what physicians say about disease is applicable here: that at the beginning a disease is easy to cure but difficult to diagnose; but as time passes, not having been treated or recognized at the outset, it becomes easy to diagnose but difficult to cure. The same thing occurs in affairs of state; for by recognizing from afar the diseases that are spreading in the state (which is a gift given only to a prudent ruler), they can be cured quickly; but when they are not recognized and are left to grow to the extent that everyone recognizes them, there is no longer any cure. -- Niccolo Machiavelli
I lifted this quote from a Right Wing News post on lawlessness in France, where police are injured at the rate of 14 per day by unemployed youths from North Africa.
Machiavelli might have been a predatory little snot, but he certainly was perceptive.