Mixing those pesky metaphors
"[It] took many months to run this thread to ground," Mr. Obama said in his address to the nation Sunday night. (Laura Meckler, Adam Entous, and Zahid Hussain, "U.S. Forces Kill Osama Bin Laden," Wall Street Journal (wsj.com), May 2, 2011)
To run to ground is to hunt or chase something to the point of capture or kill. But threads don't run, do they? Threads are pulled. Once again, the TelePrompTer let Mr. Obama down.