After teaching Math for over 30 years I have taught a range of students including some who found it 'challenging'. Even the least able were able to understand some simple arithmetic - if you charged someone $10 and they charged you $10 then nobody was better off and you were probably both annoyed. This works the same for larger numbers!
Why can't our world leaders understand this? A tariff war with matching increases will not help anyone in the long term. Get back to looking for positive approaches.
Regards,
Dennis Fitzgerald