Piers Morgan is outspoken at the best of times, but get him on the subject of terrorism and the safety of the nation and he is particularly passionate.
So when the Met Chief Lord Brian Paddick appeared on Good Morning, their discussion about the attack in Westminster was unavoidably heated.
Piers argued with his guest about how security at Westminster should be handled in the wake of last week's tragedy, which saw policeman Keith Palmer stabbed to death and three other innocent victims killed.
Lord Paddick, former deputy assistant commissioner for the Metropolitan police, told GMB co-anchor Susanna Reid: "The dilemma we have got is that we want an open parliament.
"We don't want police officers on the periphery armed to the teeth, frightening people away.
I don't care about frightening people. I care about making people feel safe.
Piers animatedly disagreed with Padick, arguing: "Why not? I do. I don't care about frightening people. I care about making people feel safe."
His guest responded: "What we do need is armed officers immediately behind those officers."
As the programme reminded viewers, there were no armed police posted to the Carriage Gates at Westminster when Islamic extremist Khalid Masood launched his murderous attack last Wednesday afternoon.
Masood was eventually shot dead by plainclothes protection officers, who happened to be waiting nearby in Defence Secretary Sir Michael Fallon's car.
(Had they not been there does not bear thinking about...)
Piers continued: "You have two unarmed cops, one of them loses his life. The guy who does it only gets shot dead because two close protection people attached to the defence secretary happen to be in the car at the time.
"If they hadn't been there who knows how many more people this man might have killed."