The 1984 IRA bombing of the Grand Hotel in Brighton during the Conservative Party conference killed five and injured 31.
MP Sir Anthony Berry was killed, along with party chairman Eric Taylor, and the wives of three Tory MPs - Lady Jeanne Shattock, Lady Muriel Maclean and Roberta Wakeham. However, Mrs Thatcher was uninjured in the bombing.
On an episode of The Rest Is Politics podcast, presented by Alistair Campbell and Rory Stewart, Mr Adams said: “There would be very few tears shed for Margaret Thatcher in Republican Ireland, or in many villages in Wales and working-class Scotland and England itself.”
Asked if he would have been happy if Mrs Thatcher died, Mr Adams replied: “Happiness or happy is not a term I would use. The fact is, there was a war.
“Margaret Thatcher was notorious, not just for her presiding over the deaths of the hunger strikers, which could have been easily resolved, by very simple improvements in the prison regime.
“But also because she was upfront, and she was being the Iron Lady, and she was masquerading as being somebody who was indomitable, and so on.
“But, it’s done, it’s over, it’s gone. All of that was in the past.”
Former soldier and Tory MP Rory Stewart challenged Mr Adams about his remarks, to which the Northern Irish politician replied: “I never went to war.
“You came to me, you know. You came in, in khaki and tanks. I think including the deaths of British soldiers and RUC officers, all those deaths are to be regretted.
“It’s a regrettable part of our history. And, clearly for civilians, for them to be killed, it doesn’t matter if it was an accident or not. That’s even more regrettable, and thankfully we’re now out of all that, and we need to learn the lessons of it.”
Following the announcement of the death of Mrs Thatcher in 2013, Mr Adams claimed the former prime minister “did great hurt to the Irish and British people during her time as British prime minister.
“Working-class communities were devastated in Britain because of her policies,” he said.
Gerry Adams stepped down as leader of Sinn Fein in 2018 after more than three decades in the role.