Fair enough. I'll tell you what I'd prefer our government's foreign policy to be, assuming we need to have a State at all. My proposal is pretty simple: Swiss-style armed neutrality. That means no invasions, no military threats, no foreign aid, no "covert operations", no military bases outside the country, no attempts to influence the internal affairs of foreign countries whatsoever.
No one blows up bombs in the streets of Geneva. No one from Switzerland gets kidnaped in third world countries to protest the evils of Swiss foreign policy. Wherever they go, at worst, people think of the Swiss as boring — it is rare that anyone feels the need to buttonhole someone from Zurich or Lugano and tell them off for what their government does.
The Swiss are not pacifists, though. They have a very strong militia for defense, and in times past when Europe was less peaceful, it would have been extremely costly for an attacker to invade them. Even if (in the case of particularly strong enemies) an invasion might have ultimately succeeded, it would have yielded very little of value at an astonishing expense.
Such a foreign policy perfectly suits the minarchist excuse for government &mdash that it exists to protect its citizens and their property from violence within the borders of the country. It is pretty inarguably perfect for that purpose. (I'm not a believer in the necessity of even a minimal state, but that's not today's discussion.)
I think the U.S. would do just fine with such a policy. It is unlikely that many countries could attempt an invasion of the U.S. given our geography. With a strong militia, armed to the teeth, no such invasion would likely succeed even if someone was foolish enough to try. In addition, we have a large nuclear arsenal, which should make any potential attacker worry about the fate of their home territory. The nuclear weapons pretty effectively deter any attempts at missile based attacks, too. Realistically, were we neutral, we would not be attacked at home if we were even moderately careful.
For a while, we might still get terrorist threats from people who hadn't realized that we had withdrawn our forces from overseas and weren't going to bring them back, but those would fade after a while. In the long run we'd be fine.
Such a policy is also far, far cheaper than the one we pursue now — the economic benefits alone would be more than worth it.
Some might argue that we would not have a force capable of deterring attacks on U.S. shipping — especially oil shipments — without a strong military capable of foreign intervention, but I don't believe that such a use for the military is good idea in the first place. For one thing, it distorts the market for commodities like oil because the market price does not reflect the true cost (including armed security) of importing the commodity. My solution would be for the oil companies to simply hire private security to guard their own tankers and leave it at that — if the cost is high, then let the market price for oil reflect that.
Some might also argue that a strong military is needed to defend U.S. citizens overseas, but I doubt that. As I noted, how often are the Swiss targeted for political reasons?
Lastly, some might argue that we have an obligation, as a nation, to defend the interests of those under the thumbs of totalitarian regimes abroad. As I've noted elsewhere, however, U.S. foreign policy has propped up and indeed created totalitarian regimes far more often than it has attacked them. This is a simple instance of the universal rule that governments don't do what you want them to do — they do what public choice economics causes them to do. We can dream all we like, but governments are made up of people with their own agendas.
Furthermore, as I've also noted elsewhere, I have no objection to people spending their own resources and risking their own lives liberating the downtrodden in the third world, or persuading others to do so voluntarily, but the Non-Coercion Principle that we libertarians follow says that we don't use force to get others to spend their money and risk their lives for our causes, no matter how noble our cause may be. Whether the purpose is curing cancer or building a football stadium, coercion is still coercion, and libertarians don't coerce others into paying or doing.
By the way, this is all pretty standard stuff. Libertarians have been advocating this position for decades, and I don't understand how it can be the least bit controversial among people of our political clan at this point.