Sir – In his “open letter” to Conservative party chairman Grant Shapps (Report, May 9), Keith Mitchell urges “I think you need to realise that local councillors are your stormtroopers and your first line of support for your members of parliament”, which it must be hoped is an ill-considered historical allusion on Mr Mitchell’s part.

The “Sturmtruppen” had their origins in small German army infiltration units deployed on the Eastern Front in the First World War, many members of which went on post-war to join the Freikorps (private armies) which, from 1921, formed the corps of the “Sturmabteilung” (SA), better known as Hitler’s Brown Shirts, from the outset infamous for their violence and brutality, not least against Germany’s Jews.

By 1934, 4,500,000 murderous stormtroopers were active throughout Germany and were most certainly Hitler and the Nazi Party’s “first line of support”, so for Mr Mitchell to describe “local councillors as stormtroopers” is abhorrent and offensive.

Even if the term stormtroopers is de-Nazified, it still means shock/assault troops, which is surely not what Mr Mitchell had in mind.

No, this is the debased and corrupting language of the extreme racist right, a million miles from Keith Mitchell’s brand of Conservatism.

A public and very open apology for “stormtroopers” should find its way to Mr Mitchell’s blog without delay please.

Bruce Ross-Smith, Headington