"What was the argument of why hydropower shouldn't be included in the definition?"

Hydropower isn't included in the definition of "renewable energy" in California either, Matt, and the reason is simple: greed.

Hydropower generates a lot of power for California. Some of it is local, but most is imported from the Pacific Northwest. Solar, wind, and gas interests have consistently argued to exclude both hydropower and nuclear from any definition of "renewable" or "clean energy" because replacing them with wind turbines and solar panels would make them a lot of money.

If that bursts anyone's bubble, it should.
 

Jim, as I've pointed out many times before - existing reserves of uranium are estimated to last 20,000 years.

If we continue to allow ignorance and irrational fear to invent spurious reasons to reject nuclear energy, however, it's unlikely humanity will last another 1,000 years. Then there will be enough uranium - and quite a bit left over!