[burfog]

No, they do not pay the tariffs.

When a marketplace transaction is taxed, it really doesn't matter which party has to hand over the money. The buyer and seller will split the cost of the tax according to elasticity. Consider a transaction that is worth $100 in a tax-free situation, using numbers relevant to the US/China tariffs:

Without tax: $100 is transferred from buyer to seller.

Buyer hands over money: The buyer pays $30 to government and $76 to the seller, for a total of $106.

Seller hands over money: The buyer pays that $106 to the seller, who then pays $30 to the government. The seller keeps $76.

You might wonder what would motivate the Chinese seller to reduce his price. He has unavoidable costs like loans. Keeping a factory partially idle is painful. There are fixed costs. He doesn't have the monopoly power to dictate a selling price. He can't force the buyer to buy.