Every nonresident alien individual to whom this section applies and who, within the 10-year period immediately preceding the close of the taxable year, lost United States citizenship shall be taxable for such taxable year in the manner provided in subsection (b) if the tax imposed pursuant to such subsection (after any reduction in such tax under the last sentence of such subsection) exceeds the tax which, without regard to this section, is imposed pursuant to section
871.