That’s... not as good as a nuclear device? Susceptibility to 10 ton tungsten rods is pretty lame to worry about when a 10 ton actual nuclear bomb would be so much worse.
A heavy object picks up some kinetic energy as it falls into a gravity well, but realistically a tungsten rod moving at orbital velocities could destroy a space station or asteroid habitat just as effectively as it could destroy an Earth target. And there'd be somewhat of a difference: with Earth, we have an atmosphere to slow fast-moving objects down and provide an early warning that something is coming at us. (Probably not enough early warning to do usefully react, but still. A couple seconds is more than 0 seconds, and maybe there's some way to use that to a tactical advantage.) In space you'd have no warning at all, unless you can track it on radar or telescope, in which case Earth could do the same.
Earth's big advantage is that everything we do is so geographically distributed that any damage done is a temporary setback. It would be a sad day, but the human race will go on. Unless it was a really big rock, in which case it would be hard to redirect one into Earth's orbit without anyone noticing.
I suppose if you really want to be protected from flying rocks, the best bet may be to find some moon or minor planet with weak gravity, and tunnel deep into the surface and set up shop there. You could do something similar on Earth, though there's a limit to how deep you can go before it gets too hot. (In Consider Phlebas by Iain M Banks, there is planet whose original inhabitants had built a deep underground subway system where train cars house the military command structure, and in time of war the trains would always be moving around so that a nuclear-armed adversary wouldn't know where to strike. That approach could work too.)
Realistically, though, I think if humanity develops the technology to start moving large heavy objects around the solar system, then almost everyone is going to be very vulnerable. The best defense is to be on friendly terms with all your neighbors, and have very good visibility into where everyone is and what they're doing.
See also The Moon is a Harsh Mistress
If you literally drop something in orbit then it stays in orbit. In order to make it fall to the ground you first need to de-orbit it.