Of all the Republican presidential candidates, only Ron Paul believes in and adheres to the American foreign policy philosophy of Washington and Jefferson. For this he, and all other like-minded statesmen over the past seven decades, have been misleadingly smeared as "isolationists." In this context, "isolationist" is truly Orwellian. By advocating peace and free trade, and only supporting just and defensive war, Ron Paul is advocating the maximum possible interaction between the peoples of the world.
The core principle of economics is that as long as there is private property and reasonably free markets, individuals, in pursuing their own self interests, will specialize in whatever they are best at, selling those things to others, and using the proceeds to purchase things which they are not very good at producing. This is how the poorest of the poor can still survive and improve their lives. There is no "survival of the fittest" mentality attached to the free market. The poorest of the poor do not need to produce their own food, build their own houses, and manufacture their own clothing (nor does anyone else): the international division of labor allows them to rely on others to provide such things so that their lives are sustainable.
War, on the other hand, "bursts asunder" the international division of labor, as Ludwig von Mises wrote in his masterpiece, Human Action. For example, during the late nineteenth and early twentieth centuries the industrial revolution enhanced the standard of living of the average person more than the previous generations could ever have imagined. Wherever capitalism was allowed to flourish the common man enjoyed the fruits of the international division of labor as his standard of living rose while his hours of work per week declined (also thanks to the increased productivity of labor caused by capital investment under capitalism). World War I destroyed all of this, throwing country after country into an isolationist abyss by all but destroying the international division of labor. The people of the world who had benefited in countless ways from the efforts of strangers were isolated from those benefits as their living standards declined. Countries became isolated from the benefits of international trade while forming political alliances to wage war with. War being the opposite of capitalism, the end result was the death of millions and the destruction of capital on a massive scale.