WASHINGTON — National Intelligence Director James Clapper is apologizing for telling Congress earlier this year that the National Security Agency does not collect data on millions of Americans. In a letter to Senate Intelligence Committee Chairwoman Dianne Feinstein, Clapper says his answer was “clearly erroneous.” Leaks by NSA systems analyst Edward Snowden have revealed the NSA’s sweeping data collection of U.S. phone records and some Internet traffic every day, though U.S. intelligence officials have said the programs are aimed at targeting foreigners and terrorist suspects overseas. Clapper was asked in March if the NSA gathered “any type of data at...