Why is PHP Composer so slow?

Question

Why is PHP Composer so slow when all I do is init a project with zero dependencies? Here are the commands I run:

composer init

Answer 1

If any of the previous answers don't work, check if your firewall allows for TCP_OUT on port 9418.

My firewall security was too sharp. This caused Composer to take so long, I never got any timeout or indication the port was blocked.