The provision in the Revenue Act of I941 (Section o109) to reduce by treaties with other countries of the Western Hemisphere the income tax withheld at source in the case of certain taxpayers resident therein reflects the movement to develop international tax law which made ever-increasing headway during the two decades subsequent to the Peace of Versailles. Progress in the prevention of international double taxation, as well as of extraterritorial and discriminatory taxation, has been realized partly through unilateral restrictions on a government's fiscal jurisdiction by internal legislation, and partly through reciprocal treaties. The United States Congress has in effect delegated, in the above provision which amends Sections 211 and 23I of the Internal Revenue Code, specific authority to the Executive to reduce the withholding rate of 27Y2% to a rate not less than 5% in treaties with countries of North, Central, and South America, the West Indies (including Cuba and Bermuda), and Newfoundland. Previously, such a reduction could be made only in treaties with contiguous countries, i.e., Canada and Mexico, and a treaty had been concluded with the former. The reduceable rate is applicable to dividends payable to corporations organized in such countries and not doing business in the United States (Section 23I (a) (i)) and to dividends, interest, royalties, and other fixed or determinable annual or periodical income from United States sources derived by aliens resident in such countries and not doing business in the United States (Section 211 (a) (i) (A)). The tax of 27?2% is withheld from the gross amount of such income derived by nonresident aliens up to an amount equal to $23,000, at which figure such taxpayers are required to file returns and pay a tax on the net amount of such income. Nonresident aliens deriving a lesser amount of such income usually bear a heavier tax than citizens of the United States in respect of the same amount of income. This discrimination against taxpayers resident in other countries was pointed out