And did you see how much it gained in the previous two years prior to that?
And who was president when that was going on?
Sure, the recent stock surges was all thanks to demented Joe Biden, and the recent innovations and unprecedented market capitalization by the American companies had nothing to do with it.

And what a coincidence that it happened just as Trump started flailing around shouting “TARIF” at everyone.
The markets actually went up when he first became president. Then everyone realised he has no idea what he’s doing. No strategy. No one knows what he’s going to do next, least of all Trump. The markets hate uncertainty, that’s why everything is tanking.
Your narrative of small surcharges on Canadian and Mexican goods causing this is a terrible take. Many of the companies affected are in sectors which have nothing to do with that, or with the physical trade of foreign goods. There have been other significant events which have occurred recently, which discredits your coincidence theory. Beyond overpriced stocks, it is otherwise far more likely that another factor driving the sell off is related to the massive government cuts and Wall Street's addiction to government grants.
Here is NY Post to set you straight:
https://nypost.com/2025/03/10/business/ignore-the-stock-market-wall-street-dealing-with-painful-detox-from-government-spending-addiction/This situation will likely correct itself and you won't have to cry and be sad about this anymore. However, I am not too sure why you are concerned and appear to care about the success of America, considering that your own country is failing significantly if we divide the US GDP by US population and compare the same to the UK GDP and UK population. By this general measure, an American is twice as valuable as a British citizen. You really should do better.