Ted Cruz has been challenging Donald Trump to debate him, one-on-one, for months. Today, Trump agreed. Or not. The Texas senator employed the trolling meme — in which a video is interrupted by a clip of one-hit wonder Rick Astley singing his 1987 song, "Never Gonna Give You Up" (a gag commonly referred to as "Rickrolling") — as his way of informing the viewer that there would be no showdown.