I remember when going with the FTA was scary. Everyone was told to adjust to the new reality and the world was not going stop revolving and they were right. I am passing back the same advice in the other direction. 
Maybe a cold shower in a tariff wall is the kind of therapy that all of the partners need. If the US wants to make their product less competitive in their largest export market then why would we care?If they want to add tariffs to the OIl & Gas they import it will only hurt their citizens.
There will be a peirod of adjusting to the new reality but we'll get over it. Pendulums swing.