Project SHAMROCK: The NSA's Decades of Reading Americans' Telegrams

The Story

During World War II, wartime censorship laws made all international message traffic available to military censors. That gave military intelligence copies of foreign traffic. With the war over in 1945, that practice was due to end, and the codebreakers stood to lose a valuable window.

So on August 18, 1945, according to the Senate's Church Committee, two representatives of the Army Signal Security Agency went to New York to meet the heads of the big international telegraph companies. Their lawyers warned that the plan would be illegal in peacetime. The companies agreed anyway, on condition that the Attorney General personally assure them they would be protected from suit, and that efforts be made to make the operation legal. The committee found no document showing the assurance was actually given. But the program began within weeks. ITT and Western Union joined by September 1, and RCA by October 9, 1945.

"In no case did NSA obtain a search warrant prior to obtaining a telegram." (Church Committee, 1976)

The arrangement was later known as SHAMROCK. In 1947, Secretary of Defense James Forrestal met the companies and told them the program was "in the highest interests of national security." They were told President Truman and Attorney General Tom Clark approved, and that they would not face criminal liability, at least while that administration lasted. An attempt in 1948 to change the law and make the program legal failed in Congress. In 1949 the companies sought assurances once more. According to the committee, that was the last time.

The program passed to the new National Security Agency in 1952. For years, couriers carried microfilm and paper tapes from New York to NSA headquarters at Fort Meade, Maryland, several times a week. One former NSA official testified that the agency received "literally miles and miles and miles of punched tape."

Then the technology changed. In the 1960s, RCA Global and ITT World Communications switched to magnetic tape, and NSA could sort the telegrams electronically. The committee noted that this meant telegrams of American citizens on NSA's "watch lists" could be picked out and passed on. From 1966, the CIA rented office space in lower Manhattan, under the guise of a television tape processing company, where NSA could copy the tapes. The CIA pulled out of that arrangement in 1973.

The scale was enormous. Two of the companies, RCA Global and ITT World Communications, provided virtually all of their international message traffic. NSA estimated that in the program's last two or three years, analysts reviewed about 150,000 telegrams a month. "In no case did NSA obtain a search warrant prior to obtaining a telegram," the committee wrote.

Few in government knew. Louis Tordella, NSA's deputy director from 1958 to 1974, testified that to the best of his knowledge no president since Truman had known about the program. The companies, for their part, could find no record of any agreement with the government.

Secretary of Defense James Schlesinger ordered SHAMROCK ended effective May 15, 1975, as the Senate investigation was under way. NSA said it was no longer a valuable source of foreign intelligence and that the risk of exposure had grown. On November 6, 1975, Sen. Frank Church read the committee's report on the program into the public record.

In its final report in 1976, the committee called SHAMROCK "the largest governmental interception program affecting Americans, dwarfing CIA's mail opening program by comparison." According to the Senate Historical Office, the reforms that followed the investigation included the Foreign Intelligence Surveillance Act of 1978, which required the executive branch to seek warrants for national security wiretapping from a special court.