That was true, and essential for American security, until this week. With his barrage of executive orders, Trump is taking America back to the historical nightmares of the world before December 1941: closed borders, limited trade, intolerance to diversity, arms races, and a go-it-alone national race to the bottom. His executive order on "rebuilding the U.S. armed forces" calls for "peace through strength," but this document and the others he signed offer nothing but unilateralism and militarization: more military spending, more nuclear weapons, more use of torture (which is illegal), and more promises to destroy ISIS and other terrorist threats. The executive orders promise to curtail American participation in international organizations, prohibit whole categories of foreigners from entering our country, and limit exchanges of ideas and goods. This is not a United States any president from Roosevelt to Reagan would recognize.

Coupled with Trump's decision to withdraw from the Transpacific Partnership trade negotiations, build a "huge" wall on the southern border, and impose high tariffs on imports, the United States is left with a foreign policy that cuts it off from the relationships that fueled its growth for 70 years. Where will the markets and brains come from, when America is isolated and reviled? Where will the capital to fund its debt come from, when it is in deep conflict with the countries that buy its bonds (especially China)? And, most significant, how can America anticipate and prevent foreign threats when it gets little help from others? Trump's executive orders are making the United States an international pariah, which raises the costs for every element of its security and economy. Self-absorbed islands never prosper, and they usually decline fast.

The Trump team seems driven by its perception of enemies more than its analysis of national interests. If the president and his advisers thought seriously about the historical sources of America's strength, they would not be so quick to destroy the liberal world order that it built. They would also think through the implications of the alternative order they are trying to create. It sounds courageous to say the United States will jettison pesky allies who do not "pay their share" and shut potential terrorists out of our country, but do those angry actions really serve its interests? Do they make America stronger, safer, and more prosperous? Almost certainly not.

By signing a series of militaristic executive orders at the Pentagon, Trump is sending a clear message that his definition of the national interest is purely focused on short-term chest-thumping and job hoarding, even as his actions will destroy more jobs in the near and long term. He shows no interest in nurturing a sustainable global economy, a livable planet, or the spread of democracy. The executive orders reveal his deep antagonism to all of these things, and the basic wisdom of American history. His actions are all about appealing to his less-than-majority base of supporters within the United States. He is intent on showing that he is boss, with "tremendous" support. The nation be damned.