How many troops would it take to subdue a planet?

[Jabber Swarky]

I think you replied to the wrong post. Seafort was talking about conventional warfare, as in people getting killed.

Oops. Fixing it now xD

[Captain Seafort]

OK. So how would we get a bloodless victory?

Not going to happen I'm afraid - war is inherently a bloody business.

[Deepcrush]

No war is bloodless even more so when you talk about taking over a planet! For total control of earth I'd say 300 million troops. Half a billion for a clear win and enough troops left over to control the surviving population. Remember that the 3rd war of Armageddon cost as many as 8 billion lives alone. A full 10% of the worlds population.

[Sionnach Glic]

Good point.
Quite simply, the numbers involved would be massive, beyond anything we can realisticaly come up with in the modern day. It'd probably be cheaper just to BDZ the entire planet, terraform the remains, and set up a new colony there. The costs for invading and occupying an entire planet would be massive. The US has problems with one small country, imagine trying to hold a whole planet.

[Captain Seafort]

It'd probably be cheaper just to BDZ the entire planet, terraform the remains, and set up a new colony there.

I don't think you can effectively terraform a BDZ'd planet - in "Spectre of the Past" it was considered cheaper to terraform an uninhabited world to Camaas' original specifications than to try and repair the original, even forty years after the attack.

[colmquinn]

If an alien species/ us suitably advanced, have enough resources and time to send troops to take a world then I'd imagine hitting the planet from orbit with some nice chunky meteors and waiting around for a few years or so till the winter effects of the impacts subside.
Land, "remove" any of the pesky still resisting population (now greatly reduced in capacity and numbers).
If nature is taking too long to bring the ecosystems back on track then just help it along a little with spreading and hurrying production of plants we took with us or samples that may have survived. No subduing needed. If I come all the way to your world and spend lots of precious resources then I'm not gonna pussy foot around and waste lives and even more energy killing you off than necessary.
Not strictly the answer to the point but what I'd do if I needed to take a planet for our uses.

If you're talking about normal current level tech on this world then I'd imagine that no amount of troops currently available would hold it for long short of genocide.

[Graham Kennedy]

I'd say it would depend on how bloody you were prepared to be about it. For instance if you had a rule that any city which offered significant resistance received a 10 kiloton nuke... I suspect things would be under control quite nicely after a thousand cities, even if you only had a very small force on the ground.

[Teaos]

If by subdue you mean to control every single thing I'd think one soilder for every 50 civilians.

But it could be done easier by just controlling the main areas such as governments ect.

[Monroe]

Well if you wanted to have a planet to rule with the most minimum forces you could give one country that hates another technology say 200 years more advanced. Then in the aftermath of the war you invade with technology 2 million years more advanced. Kind of like how the Spanish took out the Indians, divide and conqueror.

[Sionnach Glic]

I don't think you can effectively terraform a BDZ'd planet

Quite true. I have a tendancy to use the phrase 'BDZ' to mean any type of blasting the planet from orbit. In this case, I just meant wiping out all life on the planet and fixing whatever serious damage you did.

[Captain Seafort]

Cheapskate.

When I talk about a BDZ I mean proper BDZ. 8)

[Mikey]

Exterminatus! "That one may support life again - make a note to check sometime next millenium."