I doubt the Irish would agree. There’s a street in Dundalk called Scarlett Street, socalled because of the blood which flowed from Cromwell’s butchering of the Irish. He was a murderer.
Most of the Irish fought on the wrong side of England’s Civil War, and have constructed a narrative which paints Cromwell as a monster to reflect this.
Cromwell was no more brutal than any other 17th century military commander, and probably a lot more merciful than most. Especially in light of the atrocities perpetrated against Protestants and settler communities by the Confederates before and during the Civil War.
The bloodletting following the storming of Drogheda for which he is most notorious for was just according to the rules of war at the time, which stated that a garrison that refused to surrender was not entitled to any quarter by the army forced to assault them, and so it was.
At the siege of Clomnel, a surrender was negotiated after several failed assaults, but Cromwell was deceived when the garrison was allowed to slip out under cover of darkness. Despite Cromwell’s extreme anger at this deception, he continued to uphold his end of the bargain by restraining his troops from looting and pillaging the town. Many of his contemporaries would not have under those circumstances.
Cromwell was a hero, albeit a flawed one who in many instances could only do his best under difficult circumstances. And the modern world with its democracy and non-absolute government owes credit to Cromwell for winning the Civil War on behalf of Parliament.