A few thousand Turians came, a population of 29 million was reduced to double digits, a few thousand Turians left. I wouldn't call that a smackdown.
The pre-war population of the original colony was two million, and I take it you missed the bit in the Asari matron's segment about three thousand Turians going home in body bags. 29 mil is the figure from seventeen years post the war, when the planet has become a major fortified strong-point for the Alliance fleet.
Anyway, let's run the numbers.
At the start of the invasion, Shanxi had approximately two million residents, with roughly two to four hundred mass-effect weapons to share around between them by dint of the 'couple of hundred' actual military personnel noted by our Turian vet. The battle of Shanxi lasted 107 days, at the end of which Shanxi had 28 human residents. That means that an average of a touch over 18,691 humans died per day in the defence of Shanxi.
Eighteen thousand six hundred and ninety one a day. If Shanxi has a 24-hour day, which I don't know if it does but still, that means on average 12-13 humans died per
minute in the planet's defence
and they kept fighting.
Meanwhile, again at the word of our Turian vet, out of ten thousand Turians who landed on Shanxi, four and a half thousand died; going by our Asari matron's estimates three thousand of them went home in body bags, meaning there should be approximately 1500 Turian bodies somewhere in the ruins of the city. That's just over 42 dead Turians a day - a little short of two an hour, again assuming a 24-hour day.
Smackdown? The Turians lost near to half their invasion force killed at the hands of barely-armed civilians, and we know from our Turian vet that most of their casualties survived meaning that the actual casualty rate was far
far higher, I'd say their casualty rate cannot possibly have been lower than 200%. Even disregarding non-fatal injuries that's an
absolute meatgrinder by the standards of any military, anywhere,
ever.
There's five and a half thousand Turians in the galaxy today who talk about Shanxi in the same sort of a way that a great many older Americans talk about Vietnam.
The Turians may have been in a winning position when the Asari intervention came - the defenders (functionally speaking) had nothing left to give and were most likely hours away from annihilation - but it was a Pyrrhic victory at best, Turian morale on the ground was as close to total collapse as the defenders were, and the entire galaxy knows it.
In the years since the war the galaxy's got to know humans a little better, got to know that they're often quite personable, but there's always that knowledge that making humans think that they're dead anyway is a REALLY BAD IDEA, because some of them will
decide to take you with them.
