The camp commander said the two Saudis and a Yemeni were "committed" and had killed themselves in "an act of asymmetric warfare waged against us".
Many of the 500 men held at the facility have been there for three years without trial.
Mr Clinton praised "very outspoken" military officers who voiced criticism of prisoner abuses at Guantanamo on those grounds.
"There’s one thing I’d like international leaders to know about America," he said.
Recent critics of the high-security detention centre include former President Jimmy Carter and Democratic Senator Dick Durbin, who last week compared interrogation practices at the prison to those used under Hitler and Stalin.
Comment: Words fail me; words fail me…
Bush & Blair have blighted International Justice, Law, Human Rights and Social Trust, and therefore Communities’ Goodwill & Cohesion.
Latest 14/06/06 – The vindication of my claim
People in European and Muslim countries see US policy in Iraq as a bigger threat to world peace than Iran’s nuclear programme, a survey has shown.
The survey by the Pew Research Group also found support for US President George W Bush and his "war on terror" had dropped dramatically worldwide.