The US generally taxes non-US Persons on “territorial income,” not “worldwide income.” Territorial income taxed by the US includes:

• Income effectively connected with a US trade or business (ECI), and
• US source income that is not effectively connected with US trade or business.

Absent application of a superseding tax treaty, ECI, after allowable exclusions, exemptions and deductions, is taxed at graduated rates. These are the same rates that apply to US citizens,

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