John McTernan is head of political practice at PSB, a strategic research consultancy. He was a speechwriter to ex-British Prime Minister and Labour Party leader Tony Blair and was communications director to former Australian Prime Minister Julia Gillard. The opinions expressed in this commentary are his own.

(CNN) "You talkin' to me? You talkin' to me? You talkin' to me?" goes Robert de Niro's monologue in Taxi Driver.

There have been many times in politics -- and more frequently since the rise of social media -- when that has felt like the most appropriate response to an outrageous statement. But never more so than when the 2013 remarks of Jeremy Corbyn , the leader of the UK's opposition Labour Party, about British Zionists were revealed by the Daily Mail newspaper

"[British Zionists] clearly have two problems. One is they don't want to study history, and secondly, having lived in this country for a very long time, probably all their lives, they don't understand English irony either... They needed two lessons, which we could perhaps help them with."

My immediate thought was "Does he mean me?" I'm British and I'm a Zionist. I'm not Jewish -- I'm actually a Scottish Catholic -- but I am a Zionist since I fully support the right of the state of Israel to exist, the right of Jews worldwide to have a homeland and the right to self-determination.

The other words fit me too.

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