In the 19:th century there was a few years of no rain. The farmers begun to starve. No harvest and dead animals. Desperate time caused desperate measures. 20% of the total population emigrated from Sweden – to America. Similar stories all over Europe built America. Most Americans have a history of emigration. Well, everyone but the natives actually. Donald Trumps ancestors, for example, were expelled from Germany.
But you never know when it’s time to run. The melting north pole will probably make Americans run with a ladder when the ice melts. If that wall will be built.