Your Tuesday Morning Brain Teaser!

Here is your dose of the 'Tuesday Morning Brain Teaser!'  This is a tough one today.  But, it's a good way to get going on your Tuesday.I am going to be honest, I will be very impressed if you know today's question.  Here is today's 'Tuesday Morning Brain Teaser':

What was the name of the Oklahoma City Federal Building that was destroyed by an act of terrorism on April 19th, 1995?

Good Luck!