The other hope would be that the tariffs are a negotiating tool which will motivate more advantageous trade agreements for America.
Take dairy. Hypothetically Canada caves and gets rid of its supply management that assigns the US a tariff free quota for dairy products. We too revert back to a government subsidy system as in the US and EU, to keep our domestic dairy industry viable - you know, the Support Your Local Farmer ethos. The problem though is that consumers here are so pissed off at the US that they refuse to buy US produced dairy products. Canadian distributors and suppliers stop importing because the demand is not there. Consumers would rather pay a premium for Canadian or EU made products because they are not of US origin.
Once again I come back to the statement, you cannot fool the market.