Derren said:
Because thats how D&D dragons are? Why do dragons have breath weapons and trolls have regeneration? Why can Rust Monsters corrode metal?
In D&D 4, not anymore! Except of course in campaigns that use house-ruled or variant Dragons from 3rd party publishers. (Which, by the way, means that 3rd party publishers can do even more interesting things for D&D then they used to do - 3E feel, 4E rules, so to say)
But as dragons are unable to really do something big in the world without the help of magic I don't see a reason to not give it to them, especially as dragons always had magic in previous editions.
I much rather have some predefined slots for spells which I can fill or not than to make every dragon a wizard just so that he can do something else than sitting in its cave and wait to be slain.
Okay, I guess this will be the last time I repeat myself, before I wait until I have something new to add:
It is plain wrong that Dragons need magic to do something big in the world.
If a mortal man can create nations and topple kings, a Dragon can do it too. A Dragon is capable of speaking with humanoids, and he certainly has a few tricks up his sleeve to make them do what he want. If he can't do a thing on his own, he can find someone who can.
Even more important, the fact that Dragons need to rely on others make it more likely that PCs have to interact with them at all. If the Dragon is the ruler of a region, you can ask him for aid. If he is oppressing a region so he can get the slaves he needs to make his lair comfortable and safe for him, this gives incentive for the PCs to attack him in the first place.
If the Dragon is using people, some people will benefit from it (maybe the PCs want the same), and some people won't like him (the PCs have to stop it).
If he is sitting in his lair casting spells for most tasks, there is little reason to interact with him - until the point where the kings archmage decides that the Dragon constantly scrying on the king might be a bad idea, casts Nondetection or Mindblank and sends a group of heroes to slay the Dragon. Would have been nice to have some agents and spies around to watch out for this kind off stuff, or even delay, possibly stop the heroes before they wreck the Dragons lair or kill him, but well, an Alarm spell will probably do... not.