"Further research is warranted if it can be separated from the political hysteria."

Certainly, however it's far too early to make public policy based on unfounded assertion. That's purely political and lacks scientific rigor. 

We've already spent half a century (and billions of dollars) exploring the relationship between CO2 released by humans and average global temperature. To date, we have an empty sack. That doesn't mean a relationship doesn't exist, or that we should discontinue investigating it, it only means that there's no evidence any action needs to be taken.