From Federalist No. 78:
Here also the firmness of the judicial magistracy is of vast importance in mitigating the severity and confining the operation of such laws. It not only serves to moderate the immediate mischiefs of those which may have been passed, but it operates as a check upon the legislative body in passing them; who, perceiving that obstacles to the success of iniquitous intention are to be expected from the scruples of the courts, are in a manner compelled, by the very motives of the injustice they meditate, to qualify their attempts. This is a circumstance calculated to have more influence upon the character of our governments, than but few may be aware of.
Engaged judicial review serves as a Damoclean sword of sorts, nudging Congress towards acting within their constitutional authority. The sword need not drop. Rather, the threat of the sword falling is enough. Wakeup calls like Lopez, Morrison, Boerne, and others illustrate this principle all too well.
Preparing for class is way too much fun. I must’ve read this Federalist a dozen times, and every time I read it, I see more and more.