“chmod go+rw ~” breaks SSH

Quick note: running

chmod go+rw /home/ec2-user

could break subsequent attempts to SSH into the EC2 instance.

When all the usual suspects regarding SSH identity files, keypairs, etc., are ruled out, one not-well documented cause for the dreaded

Permission denied (publickey).

error could be that the default permissions on /home/ec2-user was modified.

The permissions can be modified temporarily in order to perform some tasks. However, before exiting that SSH session, be sure to restore the original ACL (0700) on that home dir lest all subsequent SSH attempts will fail.