Amazing! This is such an evocative, compelling story -- so intense that although I had waited until I had the time to read it in one go, I had to step away from the computer midway.
I felt exactly what Kelly describes above in her first paragraph -- you do such a fab job bringing to life Dawlish's fascination and obsession with great men, his unwavering trust in the god-like enormity of the institution of which he is proud to be a tiny building-block, and the not-always-so-latent homoeroticism of male circles of power. And it's great how you contrast that with Millicent Bagnold's dilemma, the inability even for her as the highest-ranking official to make the voice of reason and moderation heard among the populist clamour, with people who are willing give up freedom for what they perceive as the protection of a Great Man who offers an easy solution, not seeing that this creates facts that will set free a dynamics of their own. Crouch referring to his policy as a "burden", in true imperialist style, is another touch I found very effective.
Not to mention Dawlish's believable, chilling progression, the excellently-written POV, and the sucker-punch end.