The writer is the Eric M Zolt professor of tax law and policy at the UCLA School of Law and served in 2021-2022 as the deputy assistant secretary for tax analysis at the US Treasury

Even beyond the election year ritual of lionising the traditional industries of Midwestern swing states, both Democrats and Republicans have become increasingly intrigued by nationalist economic policy, arguing that trade policy should prioritise domestic industrial production and manufacturing jobs.

Such policy instincts are often rooted in misdiagnosis. The jobs lost due to the infamous decade-long “China shock” were far less than a typical quarter of US job losses, and the manufacturing share of employment started its downward trajectory nearly half a century before China joined the World Trade Organization. While economic discontent is real, its sources are complex, including technological shifts, declining unionisation, rising market power and changing norms and policies. Trade disruption matters, but it is far from clear that it is a dominant force.