I ask, because Christensen claims that Japan success a few decades ago was because all their successful firms (Toyota, Sony, etc etc) began with disruptive innovations, that needed to be improved, with sustaining innovations. Aiming at quality works really well for this.
He then says their recent hard times are because those disruptive innovations have now become good enough - but the Japanese firms are still improving on quality. He contrasts this with the US, where new disruptive firms are being created all the time (aided by employee mobility, VC/angel/YC non-debt funding, open markets, start-up infrastructure, largely unregulated competition, and strong IP for R&D).
US was first with mass-produced cars (Ford); Japan with games (Nintendo). Both these past innovations were disruptive.
Today, the US is pioneering consumer DNA testing (eg. 23andme), portable computers (iPhone/iPad - industrial uses are appearing, it's not just games);
The suggested case is that Japan doesn't seem to be innovating disruptively (although Nintendo has been working great at some disruptive stuff: wii and a 3D handheld). Disruptive innovation is possible in cars etc, such as the smartcar, and hybrids. Note that the all-electric car, Tesla, is from the US - and it's not clear that it will succeed. That's a big part of the disruptive game.
If anything, I'm pro-Japan, but mostly I'm a fan of disruptive innovations, and I sincerely hope that Japan will find a way to become disruptive again. Maybe it's harder because they have an aging population now... yet this could be a plus, because they could lead the world in innovations to cope with that, that the rest of the world will adopt when they catch up.
Can you give examples of Japanese disruptive innovation in planes, ships, cars? (I see your account is 14 hours old, and your comment history is a mix of intelligent discussion and reddit-style quips - I urge you to favour the former on HN).
EDIT if you are interested in constructive argument here, I'll offer some of Christensen's thoughts on disruption: it is lower-cost and/or targets non-consumers of an established product (e.g. as wii expanded the userbase of "game-players"), but it's not good enough for high-end consumers (e.g. hard-core gamers); over time it improves and replaces the established product when it does become good enough (unless the innovation is "co-opted", as Kinect is trying to do with wii).