Is it even useful to talk about 'US foreign policy' anymore? I mean, I generally hold Conspiracy theorists in marginal disdain, but aren't we seeing the machinations of a shadow authority usually beyond the concrete knowledge of the electorate in operation?

Either it's incompetence, or ruse, or a 'not-giving-a-fuck' if we know that the intelligence agencies are above the law and can act with near global impunity.

whelp. I should shut up. Probably?

There is the good part of US government staffed by great people. One example is the State Department. I imagine they are furious over this. Then there is the shadow, rogue part which is the intelligence community, full of people with paranoid delusions who will skirt the law at-will because it's for "national security."

Would that be the same State Department who sent Powell to make a fool of himself at the UN? Ok, maybe not exactly the same people, but still. The malaise is much more widespread than you think, in government and in the electorate.

Powell was the Secretary of State so I don't see how the Department itself could "send" him. He served at the pleasure of the President, who asked him to do it.

The Department provides an army of analysts and bureaucrats to support the Secretary, and its their responsibility that he doesn't make a fool of himself on the public stage by using incorrect or false data. It's well known that a lot of them did, in fact, push back on some of the absurdities contained in the initial documents provided by intelligence agencies [1], but when it became clear that most of the material was of that sort, they should have smelled a rat and should have told Powell the risk was too high. Your boss losing any credibility on the political and international stage is the worst possible scenario for any SD official.

[1] http://articles.latimes.com/2004/jul/15/nation/na-powell15

It is policy. Large swaths of the active US electorate hold their military as a sacred institution since the late '80s. The intelligence apparatus is an offshoot of that same military and enjoys the same privileges. Until the role of the US military as a whole is put into question, nothing will change. That's a political and a cultural problem, the sort of problem that political organizations are supposed to bring up and try to fix.

domestic policy too, the land of the free isn't so attractive to the potential immigrant as it once was. I don't think China is going to be filling the void though.

China does not have to win for the United States to lose.

The talented person might go to Europe, or to Canada. Or he might stay home and contribute towards the economy of his native land.