Quote from kcgoogler:
Say you are a profitable trader making say 100k. How would your taxation be in US vs Canada?
Also say you have the choice to take either Canadian citizenship or US citizenship; which one would you take?
In Canada, if you're a daytrader, and earn your income daytrading, you'll be deemed to be in the business of daytrading, and any income earned by the business will be subject to business income (NOT capital gains).
Regarding citizenship - where do you live? That'll determine where your citizenship is. IE - even though I may have access to American citizenship, as a Canadian, living in Canada, I will be taxed IN CANADA on my WORLDWIDE income.
Regarding which place has the best tax environment - probably Texas.