Mark Malek, chief information officer at Siebert Financial, said the market is more fearful of uncertainty than bad news. "A 25 per cent tariff is easier to digest than'maybe 10 per cent, maybe more, maybe less'," Mr. Malek said. "The Trump put is real, but its effectiveness is waning as traders begin to question the strategy. Tariff-driven volatility is nothing new, but this week feels like a repeat of 2018 - only worse."