It appears that Hushmail was able to turn over cleartext emails to the government when presented with a court order. This points out the importance of understanding the security model of the security tool you are using. For example, secure web pages (SSL protected) only protect the data as it moves between your browser and the remote web server. It does nothing at all to protect the data once it arrives.
Incorrect assumptions about a security model can lead you to take actions that you might not otherwise. This can put you at significant risk. Many solutions are very robust against specific threats while offering no protection at all against other threats. Understanding what is and is not protected by a solution is critical BEFORE you actually start to use it to protect important information.