TARRIFSTrump’s National Security Tariffs
Without exemptions, the tariffs President Trump imposed on steel and aluminum imports are likely to negatively impact the U.S. defense sector, critical infrastructure, and U.S. allies. How these trade-offs are weighed hinges on how national security is defined.
When do economics threaten national security? President Donald Trump has concluded that steel and aluminum imports remain a threat and is reimposing tariffs through Section 232 of the Trade Expansion Act of 1962. Without exemptions, however, these tariffs are likely to negatively impact the U.S. defense sector, critical infrastructure, and U.S. allies. How these trade-offs are weighed hinges on how national security is defined.
The story behind today’s tariffs begins in the aftermath of the 9/11 terrorist attacks, when security definitions started expanding. Previously, Section 232 cases interpreted national security narrowly and focused on requirements for defense and critical infrastructure. Just weeks after 9/11, however, the Department of Commerce argued, “‘National security’ can be interpreted more broadly to include the general security and welfare of certain industries … which are critical to the minimum operations of the economy and the government.”
That expanded concept of national security was critical for justifying Trump’s original steel and aluminum tariffs. After all, U.S. industry can meet national defense needs, which only amounted to about 3 percent of production in 2018, as former Secretary of Defense James Mattis explained [PDF]. With the benefit of a broader interpretation, however, Mattis concurred that unfair trade practices “pose a risk to national security” by harming innovation and manufacturing.
When it comes to sources of supply, however, Trump has narrowed national security. The Commerce Department under George W. Bush noted [PDF] that U.S. imports of iron ore and semifinished steel were from “diverse and ‘safe’ foreign suppliers,” especially U.S. allies in the Western Hemisphere, and viewed these reliable sources as enhancing national security. In contrast, Trump’s Commerce Department argued in 2018, “The fact that some or all of the imports causing the harm are from reliable sources does not compel a finding that those imports do not threaten to impair national security.”
The result is two competing visions for economics and security: networked versus nationalist. Both approaches acknowledge the risk of overdependence on foreign suppliers. But the networked approach distinguishes among sources of foreign supply and views U.S. partners and allies as a source of resilience. U.S. dependence on foreign aluminum (see figure 1) looks less threatening when considering that the vast majority comes from Canada.
