Republicans were isolationists back in the 'Thirties. How did that turn out? The great Bob Taft was probably the last credible Republican to embrace that discredited approach to world affairs, though that irrelevant breed of dinosaurs called Paleoconservatives and marginal types like Pat Buchanan still cling to the illusion that we're living in a world before the steamship and the airplane and the intercontinental ballistic missile, when America could afford to go its own its own way and let the rest of the world hang, and still survive.
But the community of nations required leadership even then. Great Britain largely provided it. The safety of the world has always depended on some relatively benign power with more muscle than any other single nation not so much playing world policeman (the George W. Bush model) as leading the world in taking care of its common business (the Franklin D. Roosevelt or George H.W. Bush model).
The past should be revered and treasured. But it's dangerous to live in it. There are many ways in which the (thankfully) unlikely election of Donald Trump would endanger precisely America. But his foreign policy is one of the wore worrisome ones.
HT: Real Clear World