How can you not see it? I'll lay out the obvious evidence.
Before Trump, America's Russia-friendly anti-NATO faction was entirely on the left. Even Obama, steeped in the blame-America Marxism of his college professors, started his presidency wanting to reduce American influence and not apply US pressure against Russia or Iran. He grew in office, and by year eight he had become less naive, but a lot of damage had been done by then.
Biden left most of Trump's tariffs in place. Even now, with Trump tariffs devastating the world economy, Democrats are going out of their way to defend tariffs as, essentially, good in moderation. And these are not even the most progressive Democrats. The real progressives are even more tariff-friendly.
I just argued online with a progressive a few days ago who attacked Reagan's attempt to devolve power to the states as racist. Progressives have long wanted to centralize power in DC in order so subordinate the states to their agenda.
With respect to policy, Trump is the anti-Reagan, more in line with the historic policy preferences of the left.