For "America First" to have any meaning, it has to signify something more than just acknowledging that America has interest and those should be taken into consideration in our foreign policy. Because no one has every disagreed with that, ever.

Half of America's major political parties disagree with America First in any sense of the term. Look at how the democrats go nuts at literally any policy that promotes home grown fossil fuels production, for example.

One might counter and say "But the democrats are playing the long game and are looking out for the planet" which doesn't fly when one considers the rare earth argument we're having right how: All that stuff benefits...China.

Presumably it reflects a change in our foreign and economic policy - reprioritizing the importance of America's direct interests relative to those interests we pursue by taking into account the interests of our allies. Of course that doesn't mean that we're going to start treating a nation like Canada as an enemy, but it means we're going to start treating them more as a rival for economic and foreign policy position than we have historically. Denmark as well.

It means no such thing.
What it means is that we're no longer going to willingly bankroll the lifestyles of our partners to the detriment of quality of life or America's national security posture for the simple reason that we can't afford it any longer.

But it's irrational to think that we can pursue that type of foreign and economic policy and not expect other countries to respond in kind.

The status quo in so many areas has been warped to a point so as to not be sustainable. Do you think America can keep footing the bill for defending all of Europe and Canada, all by ourselves? Forever?