Throughout his speech, FDR talked quite a bit about the American practice of isolating itself from Europe's problems…

…and then he promptly details why it's such a bad idea. (And no, it's not because Europe is awesome and supplies us with brie, baklava, and Belgian waffles.)

Isolationism was prudent during the 19th century because the world was a whole lot huger back in the days of hoop skirts and top hats. Traveling between continents took a lot of time, so it wasn't unreasonable to stay out of problems in far away places.

But in his speech, FDR emphasized the danger of isolation in a world that's much more connected than it was in the 1800s. The U.S. couldn't afford to stand around and ignore that the Axis was slowly taking over much of the European continent.

If they did, the concept of isolation would become much more than an outdated foreign policy. It would become a death sentence.