It's interesting that an investor in the "communist" Peoples' Republic of China can make millions tax-free… while investors in the United States – the supposed bastion of free enterprise and capitalism – have to pay, in some cases, a near-50% tax on investment gains.
If trading and investing is all about weighing risk and reward, then the tax code itself makes Uncle Sam the ultimate trader. He gets a nice chunk of your reward, even as he avoids your risk.
Now, I don't mind having Uncle Sam as a silent partner, but like any good partner, he should stick around to help shoulder losses during bad times as well as participate in the good times.