Trade agreements can be good or bad. Tariffs can be good or bad. Both require both careful implementation and trade-offs. No one wants to open the US market to goods manufactured without concern for worker rights, safety regulations, or the environment. No one wants to “level the playing field” only by forcing labor to the lowest common denominator and lifting regulations that protect health at both ends of the agreement.

A good trade agreement not only generates increased wealth for all involved, it does so by demanding improvements for workers, protecting the environment, and promoting human rights. It can be argued that agreements like TPP or NAFTA failed to accomplish these goals … but pushing America to the sidelines of global trade is a poor formula to either improve agreements or improve the lives of workers in America or elsewhere.

Once it goes into effect, [the TPP] is expected to generate an additional $147 billion in global income, according to an analysis by the Peterson Institute for International Economics. Its backers say it also bolsters protections for intellectual property and includes language that could prod members to improve labor conditions.

Since the United States withdrew from the TPP, China has been angling to get in. Trump’s tariffs are only making that seem like a more attractive proposition.

Even those leaders who have grown accustomed to the zigs and zags of the Trump White House say this could be different. The consequences of Trump’s targeting other priorities — the Paris climate agreement and the Iran nuclear deal chief among them — have not had an immediate, concrete effect. But the tariffs could soon put citizens in ally nations out of work, and if a trade war escalates, all sides could feel the pain, officials from Brasília to Brussels to Seoul say.

Workers are already protesting the United States in Sao Paulo. Meanwhile, as Trump makes a show of protecting the steel industry, the immediate impact of the tariffs will be felt by US workers in the last industry he made a show of “digging.” Because much of the coal used in making Brazillian steel, is mined and exported from the United States.

With Trump raising barriers while everyone else is working to lower them, there’s a very good chance that the United States will be surrounded by walls—and not just on the southern border.