Clean, mostly. With future? No, it creates primary heat. Wind and solar do not.
Water power also does not, but power from damns is not clean if you want an eco-friendly power source.
Wind currently also has a bigger environment impact than solar, but is of course a source available more frequently at night [citation needed, just kidding].
And waste we need to dispose of, which no countries has long term experience in storing. Except for costly disasters in how not to intermediately store it, here in Germany.
If the very finite amount of nuclear fuel is so useful, why not make future generations happy by preserving it for them, and for now, limiting its use until we learned how to add to the initial price the full cost of long term storage, with further disasters as a learning experience for that?
Saving lives and being cost-effective in the short run might work, but every energy expert says in 50 years, nuclear will have to be phased out anyway. And fusion could provide clean, but also primary heat inducing energy. So even that will not save us.