Because the US is such a powerful country with so much influence in the world, the president is in charge of such a broad range of things. It doesn't give citizens the ability to fine-tune US policy on each issue, so they are usually dissatisfied.
I think it would be interesting to split the presidency into 2 positions that are elected separately - a President and a Chancellor. One would set a domestic agenda and be in charge of running the country. The other would take over foreign matters, and the cabinet positions would be split accordingly under each.
Could even do 3 splits, like having a separate PM as well. If one of them does a lousy job we can fire them without giving the country a full lobotomy on the things that are still going well.
Thoughts?
It wouldn’t work… there’s too much gray area and overlap.
And constitutional originalists would say governors (and somewhat Congress) are for domestic policy, already.
This would require a huge constitutional amendment, and there are less radical but more effective constitutional amendments that should come first.