There is certainly patriotism in Japan but it is something that they are keenly aware can be very detrimental to society. Personally I think patriotism is rarely, if ever, a good thing. Mainly because it's such a thin line between patriotism and nationalism. It doesn't take much to use patriotism and turn into something very ugly. A bit like what would happen if the tea party nutters in the US ever got into power
Patriotism is based on pride and as I have discussed previously pride is almost always a bad thing. And even though pretty much every religion out there warns against pride for some reason we almost universally encourage it. As you know I'm not religious at all but even I'll admit they occasionally have some good points. And warning against pride is definitely a good point.
Why is pride pretty much always a bad thing and why do almost all of the worlds' religions warn against it? Because you can't have pride without comparison. It is impossible. So for instance you can only be proud to be American or Japanese by comparing your country to other countries. You can only be proud of yourself by comparison to others. You can only be proud of your child if you compare to other children. As soon as you start taking this step of comparison you start down the very slippery slope of thinking your country, your culture, your people, your children, etc are better than others. And this is where patriotism normally leads. To people thinking their country is better than other countries. Their people and culture are better than other peoples and cultures.
When you think of other peoples, nations and cultures as lesser to yours it allows you to do things to those people that you wouldn't do if you considered them as equals. It's what allowed Hitler to commit such incredible atrocities. It's what allowed the Japanese to commit such horrendous crimes against others in Asia. Look at the lead up to almost any war. The aggressor always stirs up patriotism and national pride beforehand.
I think in Japan they've learned their lesson on national pride and at least for the moment there's enough people left who remember how destructive it can be to keep it in check. In the future? Who knows...