could someone give me a couple of examples of what they deem significant populist legislative or executive action that has been taken over the past four or five years?
The populists haven't had much influence on legislation, but the Trump Administration used executive authority previously granted by Congress to take actions which would have been anathema to earlier Republican or Democratic administrations:
- Trump's tariffs, imposed even against strategic suppliers and allies, that were predicated on his long-held, simple-minded personal belief that balance-of-trade determined whether a country was "winning" or "losing" economically, and which had considerable resonance among his populist base;
- His Administration's withdrawal from the Trans-Pacific Partnership, a well-crafted international agreement that would have impeded China's neomercantilist trade policies but which was unpopular with supporters of his who believed it was possible for the United States to restore manufacturing jobs if we avoided committing ourselves to multilateral trade regimes;
- The continuous, concerted effort to roll back environmental regulations which were extremely unpopular with Trump's populist base (the bring-back-coal-mining crowd) and, to a lesser extent, with some conservative Republicans;
- The withdrawal from the Paris Agreement on climate, which was ideologically repugnant to the far right and, again, to some conservatives who had reservations about its terms;
- His attempts (admittedly mostly futile) to pressure companies into relocating their foreign manufacturing operations to the United States.
Some of Trump's arguably populist positions, particularly his disdain for NATO and his demands for withdrawal of U.S. military forces stationed in other countries, may have been motivated by ideology, but given his bizarre attitudes toward Russia and his fawning behavior with respect to Vladimir Putin, there may have been other reasons for them, as well.