Bruce Schneier has a great post on issues with CALEA-II.
He talks about two main issues, with historical context.
First, about the vulnerabilities that automated eavesdropping backdoors always create in communications, and how that disadvantages US companies.
Second, about the fact that law enforcement claims of communications "Going Dark" are absurd given the treasure trove of new surveillance information available through social media, and cloud services (like gmail).
I know I have talked about this issue a lot over the years, but I am shocked that I can't find any posts like it on this blog.
Bruce does it really well in any case.