When does the clock for long-term capital gains start? Better solution: the US tax code should eliminate the short-term/long-term capital gains distinction and

When does the clock for long-term capital gains start? Better solution: the US tax code should eliminate the short-term/long-term capital gains distinction and just copy the model used in Canada (and elsewhere, I'm sure): capital gains are taxed as ordinary income at a rate of 50¢ on the dollar. So $2 capital gain is equivalent to $1 of ordinary income. The usual rules apply for day traders and such where their "capital gains" are active rather than passive income. The rate doesn't have to be 50 cents - it can be 40 or 60.