The bill bans the construction of a new embassy in London and bars the State Department from closing the chancery at the U.S. Embassy in the Holy See and merging it with the one at the U.S. Embassy in Rome for security reasons, a project first pushed by George W. Bush's administration.
This one was so dumb I never even bothered writing a post about it back when it first became yet another right-wing pet rock. Long story short, the Vatican requires countries to have separate embassies in Rome for Italy and the Vatican. They don't want to be just an office in a country's Italian embassy. But the United States has an entire compound in Rome, and after 9/11 security obviously became a big issue for American embassies. So the Bush administration came up with a plan to move the Vatican embassy inside the compound, where it would have its own building and its own street entrance and save money in the bargain. The Vatican went along with the plan, and for years no one cared until the plan was officially signed off last year. Of course, Barack Obama was president by that time, but I'm sure that had nothing to do with all the outrage about downgrading Vatican relations or being a slap in the face to every Roman Catholic in America. Nothing at all.
Anyway, apparently it's back. The 2014 spending bill is chock full of conservative pet rocks, presumably designed to mollify all the tea partiers who are unhappy at the passage of a spending bill in the first place. It probably won't work, and in the meantime it bollixes up US governance for no serious reason. As Benen says, "Good ideas fail because of right-wing paranoia that congressional Republicans take seriously, and bad ideas advance because of right-wing paranoia that congressional Republicans take seriously. We can no longer focus on what is true; we must also consider what far-right media perceives as possibly true."