The last great hope for the bears is that the US is actually just like Japan in the 1990s after that country's real estate bubble burst. The chart of the current NDX and the Nikkie in 1991 look very similar. After a strong 23% rally off the bottom, the Nikkie looked like it would run higher after piercing the 200-day moving average. However, the breakout failed.
That breakout in the Nikkei turned instead into a head and shoulders top. The Nikkei subsequently retested the lows later that year.