Manuel Noriega. Pound for pound not the highest on the "ruthless" scale. I mean ok, he was Commander of Panama Defense Forces and de facto ruler of Panama from Aug. 12, 1983 to Dec. 20, 1989. Not sure what half that sentence meant, but what I do know is he was convicted on April 9, 1992 on eight counts of drug trafficking, money laundering and racketeering. So I feel like that bumps him up on the scorecard.
And speaking of cards, you can now own a piece of Mr. Manuel history. The above 1963 Christmas Card is actually autographed by the grand ruler himself. The price for this killer prize? $799.00 @ History for Sale.