RICHARD PERLE IN 1970
"In mid-October 1970, Kissinger testified, when a second wiretap was
authorized for Helmut Sonnenfeldt, who was then Kissinger’s closest
friend on the NSC staff, his role was even more tangential… was a
summary of a wiretap on the Israeli embassy in which Richard Perle, a
foreign policy aide to Senator Jackson, was overheard discussing
classified information that had been supplied to him by someone on the
National Security Council staff… Kissinger, perhaps seeking to ward off
a Nixon explosion – had handed him (Haldeman) the FBI wiretap on the Israeli Embassy and requested that the FBI be assigned to determine which NSC staff member was in contact with Richard Perle.
Kissinger had to realize that Haldeman and Hoover would suspect Sonenfeldt, who was known from previous wiretaps to have close ties to the Israelis and Perle."
Source: Seymour M. Hersh, The Price of Power (New York: Summit Books,
1983), pages 321-322.