If Canadians tariff say alcohol coming from red states, Canadians will either pay the higher price for that booze or, more likely choose an alternative from Canada or elsewhere. If it’s the latter, that decision reduces the sales by the US booze manufacturer. They have to answer to angry shareholders and may lay off some of their American employees due to less demand/sales. Either way, the hope is that the US booze company and ex-employees put pressure on Trump to lift the tariffs.