I trade in Japan and it seems that there are a lot of limitations in how trades are implemented. On most stocks there are limits on how many trades you can make in one day. If you purchase once and sell, then you can make another purchase but you can't sell it off in the same day. This is really awkward if you timed something wrong, or you like to dip in and out. From what I gather these restrictions are generally absent from the US markets, giving you a lot more flexibility in how you trade. (Btw, I'm a newbie, who started in summer last year, switched to paper trading after the collapse in October (but held on to some financials I had - thankfully recovering) and restarted in April this year).
That's strange, you'd think they'd let people trade MORE so they lose more money and brokers make more commissions. Does that rule apply only to Japanese stocks or to US stocks as well (so you're affected just because you're physically trading from Japan)? Not being allowed to sell is the most idiotic thing I've ever heard. I understand why MAYBE after too many round trips you wouldn't allowed to BUY, but not being allowed to sell and close your position? That's like forcing you to lose money.
I've never traded US stocks from Japan; from what I gather it seems difficult to establish an international account if you're not based in the US. Time differences also make it difficult from a day trading standpoint, though London has feasibility for this. Seems to apply only to Japanese stock.