What do you mean, no one to purchase our goods? There are 340 million Americans. That's a lot of people to purchase our goods.
And that's assuming that we don't have any foreign markets. Which is a bad assumption.
Getting our trading partners to lower their tariffs on US goods is a good thing for the US. Which is the point of the tariff threat. Trump has been quite open about this. His goal isn't to have high tariffs on imports to the US, his goal is to get others to have lower tariffs on imports from the US. US tariffs are the leverage he's using to try to make that happen. And he might succeed. He's going to piss people off, but that's hardly the only important metric. When someone is taking advantage of you and you stand up for yourself, that will piss them off, but oh well.
You seem to be rather inconsistent here. You think Europeans won't buy American goods because they don't like America, but you expect Americans will keep buying Chinese goods despite not liking China. Why? Are European consumers more noble, more principled, more patriotic than American consumers? No, I don't think so.
Europeans won't buy American goods if their tariffs make our goods too expensive. They will buy American goods if our goods are competitive on price. That's why Americans buy Chinese goods, because they are competitive on price. They may bitch and complain, but if the price is right, they will still buy. That's how trade works.