Senior White House officials dealing with Mr Gerry Adams, found he "would never reveal the exact nature of his dealings with the IRA (in which he clearly still had great influence)".
Mr Anthony Lake, national security adviser to President Clinton until 1997, writes in his new book Nightmares that he found the Sinn Fein president "remarkably open in his moods - either hopeful or discouraged about future flexibility in their [IRA] position . . .
"I could never be sure whether he [Adams] was having us on and was simply the human face of the IRA, as some British analysts contended, or whether he was trying to bring the IRA along to a peaceful future in which Sinn Fein and Adams himself could be at the political centre of things."
Mr Lake, who was later appointed director of the CIA but withdrew because of Republican opposition, writes that he inclined to the latter view.
Describing the events leading to the granting of the first US visa to Mr Adams in 1994, Mr Lake says British intelligence and the FBI "did all they could to convince us that Sinn Fein and the IRA were both one and the same - and irrevocably committed to terrorism".
At one meeting with a senior British intelligence official "I pressed, as tactfully as I could, for evidence of their absolute view. Little was forthcoming. I noticed their ambassador, in a rare unguarded moment, looking acutely embarrassed". Describing his dealings with the Rev Ian Paisley, Mr Lake writes that he could be "rather engaging at his most outrageous moments".