On the campaign trail, Donald Trump has railed against the effects of free trade and globalization, denouncing trade deals as bad for American workers. In his 2008 book however, Trump seemed to concede that globalization was here for good, writing, "No one can afford to be isolationist anymore."

"Globalization has torn down the barriers that have formerly separated the national from the international markets and one result is that affluent foreigners have been drawn to real estate in the United States," Trump wrote in Never Give Up: How I Turned My Biggest Challenges into Success, a book from Trump University.

"The important thing to consider is that more and more there is an interdependence of world economies," he continues. "No one can afford to be isolationist anymore. For many years, many Americans have had second homes in foreign countries, and now the trend, as Penn points out, has hit our shores. This is nothing new, but it’s relatively new to us. I think it’s a harbinger of things to come, and when I first went with condos years ago, I knew it was a timely thing to do."

He concluded, "My point is, I had been keeping up with global events for years, and it wasn’t that hard for me to see this trend coming. I’m not clairvoyant, but I take the time to be well informed. You can and should do the same thing. Spend some time on international events, read books, and keep ahead of what’s happening. Catching up can waste a lot of time—having some prescience can save you a lot of time. Keep your focus global and you may very well find yourself ahead of the game."

Trump followed up on this theme in his 2011book co-authored with Robert Kiyosaki, in which, as BuzzFeed News previously reported, Trump said the 2008 financial crisis swept the old "industrial age" economy away.

Wrote Trump, “the economy will come back, but it will not be the same economy. The old economy of the Industrial Age is dying, and a new economy of the Information Age is emerging. The rules of this new economy, an international economy, will not be the same.”

Trump acknowledged the idea further in a 2014 op-ed for CNN, first reported by Mother Jones. Trump noted, "we will have to leave borders behind and go for global unity when it comes to financial stability."