Nothing sucks the wind out of the presidential campaign announcement sails like a little copyright law dispute. As noted by Vox's Andrew Prokop and detailed by The Washington Post, Rand Paul's official announcement video was suspended thanks to YouTube's "Content ID" system. It automatically checks videos that are uploaded to the service against a backlog of copyrighted content, and alerts the rights holders when it finds an infringement. When that copyrighted material is used without permission, the companies or individuals who hold the rights can choose what happens to the offending video from a number of options, like selling ads against it, muting the audio, or — perhaps the most dastardly considering Paul's stance on the NSA — gaining access to its viewership statistics.
WMG could have trolled Paul by tracking viewership statistics instead
The rights-protected content in question here is a song called "Shuttin' Detroit Down," a country tune by John Rich about the effects of the financial crisis of 2007-8 on the Motor City. (The song has an incredibly dramatic video of its own starring Mickey Rourke and Kris Kristofferson. Seriously.) Warner Music Group holds the rights to the song, and somehow the nuclear option was deployed: Paul's entire video was blocked from YouTube. It's not clear when or if the video might return, but his staff will presumably have to petition both YouTube and WMG to allow that to happen, or find a way to change how the song was used. Until then the announcement video, like the fictitious plant in Rourke and Kristofferson's Detroit, remains shut down.