Look at the latest edition of QJE. You will see mostly studies addressing a particular policy question, e.g., 'what was the effect of this policy change on unemployment' which they answer using randomly controlled trials or quasi-experimental methods. Which aspect of this falls apart when you prod it?
Of course it is. Economics uses to be called political economy for a reason. The idea that economics can be considered separately from politics is laughable.
Quasi-experimental variation refers to situations in which assignment of treatments is 'as good as random' but treatments weren't assigned by the researchers in an RCT. A classic example is Angrist and Lavy https://www.google.com/url?sa=t&source=web&rct=j&url=https:/...
