Donald Trump has been touting staunchly protectionist and isolationist rhetoric on trade policy throughout his campaign. Whether this was merely campaign-talk is still to be seen.

However, at his core, Trump is a businessman. In the business world, isolationism is synonymous with self-destruction.

So when Trump brandishes protectionist rhetoric and sullies the role of international trade, he’s ignoring the fact that, in international relations, trade also serves as an expression of diplomatic goodwill and a means for constructive connectivity. Trade could also promote and advance free market principles abroad.

Take China, for instance. Beijing is embarking on a new era of “economic diplomacy”: trade and foreign investment have become the preferred tools for engaging with the international community, as well as for boosting domestic economic growth. China’s relatively new $1 trillion New Silk Road trade and investment initiative spanning several countries and continents attests to just that.

Instead of taking the opportunity to forge beneficial economic and trade ties with Beijing, Trump is instead threatening to impose high tariffs on China and declaring it a currency manipulator. However, doing so would actually isolate the United States’ economic interests rather than “protect” them, especially in the long run.

Trump will now have to quickly transition from a businessman into a statesman. In the business world, there is something to be said for taking a tough, zero-sum approach to negotiations. But in international relations, flippant threats and tough-talk—especially when it comes to the world’s second largest economy, as well as a nuclear power—is tantamount to recklessness, and likely to cause more harm than good.

Lastly, there are reasons to doubt whether Congress will comply with Trump’s trade and foreign policy stance. Members may instead insist that trade within a mutually beneficial arrangement, and not economic isolationism, will lead to more U.S. jobs and overall economic growth.