President Donald Trump is shocking America… by doing exactly what he promised. On Monday, the president imposed a 25% tariff on all steel and aluminum imports. As a result, the market plunged. The S&P 500 slid 2.7% (its worst day of the year), the Dow Jones Industrial Average fell by 2.1%, and the Nasdaq by 4%. Wall Street investors are anxious about what Trump’s tariffs will bring. Yet Trump predicted such market volatility last week in his joint address to Congress, saying, “There will be a little disturbance, but we are okay with that.”

On the campaign trail, Trump repeatedlypromised that he would impose tariffs if reelected to the White House. At a rally in Flint, Michigan, Trump threatened to levy a 60% tariff on goods from China and a 20% tariff on all other imports coming into the United States. Did Wall Street assume Trump was bluffing?

None of Trump’s actions should be a surprise to anyone who’s been following him. Trump campaigned on imposing tariffs because they are an essential part of his “America First” ethos. Unlike those on Wall Street, Trump believes that the interests (read profits) of America’s multinational corporations should be subverted to the national interest (read American wages).

“For years, the globalists have been ripping off the United States,” Trump told Fox News Host Maria Bartiromo in a recent interview. “They’ve been taking money away from the United States, and all we’re doing is getting some of it back and we’re going to treat our country fairly.”

In that same interview, Trump announced that one of the world’s largest shipbuilders, CMA CGM Group, is planning a $20 billion investment into the United States by expanding its American operations and creating 10,000 new jobs. Trump also mentioned that automakers Honda and Toyota are opening new manufacturing plants in the United States to avoid tariffs.

By imposing steep tariffs on imports, Trump is forcing multinational corporations to bring their manufacturing plants back to the United States and hire American workers. With universal free trade, American workers are competing against low-wage workers in foreign countries. This causes companies to offshore jobs to foreign workers or pay Americans at the lowest possible wage to remain competitive. Tariffs, however, remove the competitive advantage of low-wage foreign labor and force companies to hire American workers for fair pay. This is in essence, an America(n) First economic policy.

While Trump’s tariffs are an important tool for protecting the interests of the American worker, they also are crucial to boosting national security.

“He’s imposed steel and aluminum tariffs now on virtually the entire world, and the reason why is not to punish those countries,” Secretary of State Marco Rubio explained to reporters on Wednesday when asked about Trump’s tariffs. “It’s because he has outlined the need to develop a domestic capability. If you don’t have steel and aluminum, you can’t build warships, you can’t build airplanes, and you’re not an industrial economy.”

Massive trade deficits make the United States dependent on imports from other countries. This undermines national security because America cannot sustain itself, i.e., manufacture basic items, not to mention high-tech weapons of war, without relying on another country’s manufacturing prowess. For example, China is the world’s largest shipbuilder, while the U.S. share of the shipbuilding market is just 0.10 percent. Per the Center for Strategic and International Studies, the erosion of American shipbuilding capability “poses an urgent threat to military readiness, reduces economic opportunities, and contributes to China’s global power-projection ambitions.”

And it’s not just shipbuilding that China possesses an advantage over the United States. America imports over $500 billion worth of goods – mainly advanced technology – from China every year. With that kind of import dependency, China has serious leverage over the United States in any prospective military conflict. This is why boosting manufacturing is so vital to American national security.

“The president feels strongly — and I personally agree — that we have made some decisions when it comes to trade policy that have led to the deindustrialization of America and have left us deeply vulnerable to any sort of interruptions in global supplies or it being used to extort us,” Rubio underscored. “Not to mention our inability to produce things that we need for our own economy and defense.”

The United States must once again restore its industrial self-sufficiency, and Trump’s tariffs will do that. Not only will tariffs increase domestic manufacturing jobs and wages, but they will also revitalize American industrial production, weaning the country off the imports of potential adversaries. While this may cause some short-term pain and restructuring — especially where Wall Street is concerned — it is worth it for American prosperity.