There’s something I heard that I can’t get out of my mind. It’s one line in a very long book full of other very good lines. This was the audiobook of Ian Kershaw’s seminal biography of Adolf Hitler. It’s absorbing, exhaustive, fascinating and alarming in equal measure. But there is this one line that won’t leave me alone. I was driving on a bleak day on a country road when I heard it for the first time. I instantly rewound to hear it again, and then again. And then when I got to where I was going I bought the book itself so I could see it as well as hear it. The line torments me still. And since a problem shared is a problem halved – or whatever the expression is – I ask you to bear the burden with me.

It comes in a chapter called The Beerhall Agitator, about the absurd-looking little rabble-rouser’s activities during the early 1920s. As a kid I always wondered how they could all have been taken in by such an apparently ludicrous man. The awful truth, of course, was that enough people thought him ludicrous for this ludicrous man to be calamitously underestimated.

It invariably feels lame, swivel-eyed or just plain wrong to compare any modern politician to Hitler, but this line, written by Hitler himself of his beerhall agitator years, makes my blood run cold most days these days. There’s more than one failed, incumbent or potential leader who regularly brings it to mind.

“It makes no difference whatever whether they laugh at us or revile us … whether they represent us as clowns or criminals; the main thing is that they mention us, that they concern themselves with us again and again …”

I’m now on the lookout for something a bit lighter to read, before I go mad with fear.

• Adrian Chiles is a broadcaster, writer and Guardian columnist

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