Anyone have a good (brief) resource I could read on why that happened and why it still hasn't recovered?
Wild speculation that Japan's economy (Toyota, Sony, etc) was going to take over the entire world, without regard for the underlying fundamentals of those companies or the population that supported them. Nikkei prices increased roughly 40%/year for like six years in a row before the crash, and every (non-Japanese) financial press in the world was decrying the Japanese takeover of the global economy. But those companies paid crazy high dividends, extracting market value as cash payments to stockholders while depressing stock prices, had significant pension liabilities, and were unusually dependent on continued technological innovation, unlike a company like Unilever that is profitable for decades without changing much of anything.
There was rampant speculation in every market, fueled by accommodating financial policy, which was then abruptly cut off when the central bank freaked out and got overzealous. It wasn't just a market collapse, it was an economic collapse. Wages fell. GDP fell. Real estate crashed. Deflation caused people to hoard their money instead of spending it, making the problems worse. Companies that had expanded rapidly during the good times by taking on debt were suddenly unable to service it, and there were waves of Bear Stearns-style bankruptcies.
American stock bears typically point to the Japanese stock crash as a worst-case scenario for the US, but what they're really talking about isn't a market price decline, it's an economic failure. Yes, the US stock market could go the way of the Japanese stock market, but only if the US is replaced by some other global superpower. It would take a fundamental restructuring of the entire global economy for the S&P500 to turn into the Nikkei. It's not part of the normal business cycle, it's an example of a country dropping off the superpower list.