It is called living with uncertainty.
Being an immigrant (or "alien" as Americans like to call us) in a foreign county you are subject to their rules/laws and they are subject to change the rules and laws as they see fit. As Nelsona mentioned, this existing long before the threat of cancelling NAFTA and the rise of Trump.
If you don't like living with the uncertainty, start looking for job in Canada and quit your US job and move back to Canada asap.
For me, I have learned to accept the uncertainty, as it is out of my control. I am working for a good US employer who will support me the best they can.
I sold my house and two cars in Canada, moved my family to California more than two years ago. I am committed to make this work.
But I do understand there is risk. I am leasing a home, not buying, One of my two cars here is ten years old so I can sell it quickly if needed, etc.
Everybody has different levels of uncertainty they can accept. It is up to you.
