What prevents Chrome from running a simulator of Android, and web pages to embed an Android app that will execute, replacing the web page it came from?

That would be exactly like the Java applet, except with a much better API (and touchscreen laptops would finally make sense).

I've seen many and worked on one in the late 90's that could out do any HTML5 app I've seen or written. We did it with cohesive API's of the caliber of Windows API but multi-platform and web transparent. Those who wrote off applets will not be looked upon favorably by history.

I wrote a powerful database GUI as an applet, to pick up an update all the user had to do was save their work and hit the refresh button. I used Symantec Visual Cafe.

So? If the Java applet was not proprietary, slow and crappy, and if Sun got GUIs and applications, it would be a good thing.

And none of the above are necessary elements of a reinvention.

In fact, it's the current web one-page-app mess that is a re-invention of the notion of the Java applet warts and all: it's slow, has crappy GUI support, and it's a mess to develop in (like Swing was over-engineered crap).

We could use an actual sandboxed, "runs code from internet resources" platform, that contains the whole stack rethought and simplified.

Like they say, there are no original ideas. At some point the W3C needs to give some serious thought as to how to do applications on the web the right way. That's roughly my wishlist for the future.