People invest in the stock market because they want to make money, no one WANTS to sell stocks. Every day I see people write about how they don't understand why the market isn't selling, etc., etc. it's because of FOMO! it's because they are using the stock market to make money (as everyone is) and they don't want to miss out on anything! Add to this a president who has gone back on many of his plans and it's obvious why there hasn't been any severe selloffs. If you had sold everything during the whole tariff mess last year, you would've missed out on a whole year of gains.
Now I do think this situation is going to be different from the tariffs because the decision is not in Trump's hands like the tariffs were. He's doubled down on his most recent deadline and Iran has rejected every ceasefire proposal it's been offered. It's basically looking like the Middle East (along with a lot of its oil production) is going up into flames tomorrow. However, even though I believe this it's still not shocking to me the market isn't crashing, purely based off the uncertainty surrounding this due to all the BS headlines.
And you can see this indecisiveness in the data too; trading volume was down 60% from average today. I'm assuming this is because most traders are waiting to see what will actually happen tomorrow before they make any early decisions. No financial crisis ever saw the stock market go straight down, it's always a bumpy ride, so if this is the beginnings of one (and it looks like it is as far as my amateur opinion can see) then you permabears are going to drive yourself crazy if you don't understand this simple fact.