What Made the Raj Go Respectable?

I can't remember when I've had a book that was such an easy, absorbing read as this one that I glommed onto last month in London--Plain Tales from the Raj, an assemblage of oral-history recollections of life for Brits in India during the last generation of the Empire, i.e., before 1947. It's all assembled by one Charles Allen, otherwise unknown to me, apparently put together for some sort of BBC special back in the 70s.  The timing couldn't have been better:  a generation after the handover of power (i.e., 1947) there was time enough for most people  to have forgotten whatever they knew on the topic, and just in time to catch the first-person observation of the survivors before the onset of rust and rot.

There are many delights here but let me restrict myself to a central puzzle.  That is: by (I think) virtually universal assent the Brits, whatever their vices, gave India a kind of good government: mostly competent and almost entirely honest, in the sense that there was virtually no hint of the kind of palm-greasing and favor-selling you might expect in in this kind of bureaucratic state.

That's wonderful and the sheer nostalgia value of such a story is justification enough for enjoying it now.  But step back a moment:  whatever their sense of civic duty in the 20s 30s 40s, it certainly didn't start out that way.  Quite the contrary: the first Brits to arrive in India (in the 17th Century), practiced an unsavory mix of banditry, piracy and thuggery, all under the aegis of commerce.  It was in these early years that we observe the legendary fortunes carried off by the likes of Hastings, Clive and Pitt who got their way pretty much by just helping themselves.

Apparently there was still a fair amount of corruption (though not nearly the wealth) among the purely commercial classes in the 19th and 20th Century.  But the bureaucracy and the quasi-bureaucratic army seemed to have stayed pretty clean.  The puzzle is: why?  Or how?  It's a bit like the question of what turned the Vikings from one of the most warlike peoples on the planet into one of the mast pacific?  So with the Brits: when does a buccaneer morph into a model of virtue? And can we have it bottled and wholesaled and distributed widely around the world today?

[Note:  for a headline, I was sorely tempted to use "Big Bad Raj is Sweet Rajah Now," but no, it really doesn't make any sense to me either.]