One depressing thing that’s become clear from the Iowa caucuses is that we’re entering truly uncharted terrain when it comes to the flood of unregulated ads that will soon wash over the electorate. BuzzFeed reports that the Super PAC backing Mitt Romney far outspent rival groups in Iowa, sinking nearly $3 million into ads slamming his foes in just this one contest alone.

That’s far more than the $1.4 million Romney’s actual campaign spent in the state, and it prompts this observation from Andrew Sullivan about what’s to come from the pro-Romney forces in the general election:

No candidate has relied more on these shady organizations which can hurl negative accusations without any candidate accountability. This will surely be the general election strategy: a stream of McCarthyite attacks on an allegedly treasonous president from sources who can remain completely anonymous.

Romney himself has already tipped his hand, resorting to a stream of attacks that are designed to hint that Obama harbors indifference or even hostility towards the foundations of American life as we know it. Indeed, Romney claimed today that Democrats will continue to “poison the American spirit” and suggested that Obama doesn’t want the United States to be “one nation under God.”

As Jed Lewison notes, this is Michele Bachmann-level crazy. And Romney has to be relatively restrained; imagine the depths pro-Romney Super PACs and other outside groups that can attack without implicating Romney himself will sink to in the general election.

Making things worse, few of the millions and millions of dollars in claims will ever be scrutinized by national or local media outlets. There will just be too many claims to keep up with, and news outlets have shown little appetite for taking this on in any case. There’s precedent for this: During the 2010 elections, groups like the Rove-founded Crossroads and the U.S. Chamber of Commerce blanketed the airwaves for months with falsehoods and distortions that mostly passed under the national media’s radar. This time, it’s going to be much, much worse.

Before you shout, “Dems are going to do it, too,” let me add: Yes, Priorities USA is planning to spend around $100 million on ads on Obama’s behalf. But Dems tried to pass the Disclose Act, which would have limited such activity, on themselves, too; Republicans opposed it. And at any rate, there will be no media effort to determine which side is lying or polluting the discourse more egregiously.

So in sum: We are going to see hundreds and hundreds of millions of dollars worth of ads bombarding millions of voters for months on end, with no knowledge of who is paying for them, no accountability at all for the candidates who are directly benefiting from them, and no meaningful effort to rebut the countless lies, distortions and sleazy attacks they’ll be leveling on a daily basis — ones that will directly impact who controls Congress and the White House next year.

Welcome to Super PAC Nation.