Tariffs ought to hurt sales because those costs will naturally be passed on to the consumer. Or at least, that's what you would expect normally. What if the general investing public realizes this though, and continues to keep buying and buying and buying the SP500 so that they can grow their wallets and hopefully (in their minds) outpace the impact of tariffs? This could feasibly turn into a virtuous cycle until either some black swan or crash, or until tariffs all go away from future legislation or from being done away with for whatever reason.