"I don't think I've got it right over the last 10 years," he said in an interview with the Daily Telegraph.
Referring to the row over the installation of practising gays as bishops, starting with Gene Robinson in New Hampshire in 2003, he said: "It might have helped a lot if I'd gone sooner to the United States when things began to get difficult about the ordination of gay bishops and engaged more directly."
The Archbishop also said that the Church had been "wrong" in its treatment of homosexual people and had "not exactly been on the forefront" of pressing for civic equality.
However he criticised the Government for its "inadequate consultation" with the Churches over wanting to legalise gay marriage.
The Archbishop was upbeat about relations between the Catholic Church and the Anglican Communion, but said he doubted "that we're any nearer institutional reconciliation".