You'll want to contact the Mail admin and tell them about the problem. My guess is the website they linked to has failed to update their certificate and the WhiteHouse isn't aware of it.
Firefox's ability to tell you about unsecured sites is a "good" thing.
Hope this helps.
Grif
When I used a link in an email to me (and others like me who had signed up for the service) from the White House staff to access a certain web page, I received the following message in Firefox:
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This Connection is Untrusted
You have asked Firefox to connect securely to click.mail.whitehouse.gov, but we can't confirm that your connection is secure.
Normally, when you try to connect securely, sites will present trusted identification to prove that you are going to the right place. However, this site's identity can't be verified.
What Should I Do?
If you usually connect to this site without problems, this error could mean that someone is trying to impersonate the site, and you shouldn't continue.
This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox only connect to it securely. As a result, it is not possible to add an exception for this certificate.
click.mail.whitehouse.gov uses an invalid security certificate.
The certificate is only valid for the following names:
*.s6.exacttarget.com, s6.exacttarget.com
(Error code: ssl_error_bad_cert_domain)
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How do I go about "instructing" Firefox to allow access to the web site?
Thanks!

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