I remember going to a Dutch pub once in London and they served horse meat. We didn't try it though, we were just there for drinks.
I don't mind beef tartare as I like my steak medium rare anyway, not sure about horse meat. I guess if the Japanese serve it, they've probably breed them very well.
Interesting about the Dutch. Are they known for eating horse??
Even though it's Japan and probably way safer, eating raw meat still scares the crap out of me. Any parasite, bacteria, etc. could be in it and ruin your day. I ate it to please my host and have a laugh, but as I get older these types of things aren't as much as a laughing matter. The cooked horse was no problem, just felt bad about it....