[mvpel]

You're missing the point on an amendment. Art. 1 Sec. 8, limited the government's actions on collection of taxes (Clause 1). The 16th Amendment changed that restriction. In order to presever the document, ammendment to the Constitution do not go back and strike or insert words in the original text. When there is a conflict, the most recent Amendment wins. Looks at 18 and 21, or any of the voting rigths and elections issues.

Congress didn't need the 16th Amendment to be able to tax incomes. The income taxes that were imposed prior to the enactment of the 16th Amendment were frequently being mistaken as a direct tax, rather than its true nature as an indirect excise tax on a taxable activity measured by the income produced from that activity. The 16th Amendment did not expand Congress' taxing power, it just codified income taxes as indirect, which they fundamentally already were.

However, can you tell me whether Congress has the power to tax a citizen of China living and working in China? If not, why not?

[NYFriend]

The US would be unable to collect taxes on Chinese citizen in China, because China is a sovereign power. States (American States) are not truly sovereign because the are legally and politically inferior to the federal government.

An income tax, in all its forms, is a direct tax. Excise taxes are different. There was some archaic excise tax concept that essentially defined it as any indirect tax on something not realted to real property. But the real nature of an excise tax has more to do with the fact that it's independent of value. That's really the key, if the income tax was $10 per person per day worked, it would probably hit the definition of an excise tax.