A person's hidden costs are often the most damaging type since important decisions are made without taking them into account. This is certainly true on a national level as well. Auto manufacturers and oil producers are the source of many hidden costs in terms of air pollution, environmental destruction and global warming. These giant corporations make billions by transferring hidden costs to you and me.
The Defense Department is another hidden cost. Of course, we need defense. But do we need to spend close to 400 billion dollars on it per year, more than the rest of the world combined? That huge expenditure is only necessary if you look at what the Defense Department actually does, and that is to insure that US corporate interests are predominant in the developing world. When poorer nations decide to charge more for their fruit, labor, oil, etc., the CIA tries to overthrow their government. If that doesn't work, it is time for the US military.
History will look at the long list of US backed coups and invasions as what they are, the dirty side of empire building. And US corporations have benefited hugely from this military dominance of the rest of the world. But the hidden costs to you and me are there as well. This country spends such an enormous amount on its military that there isn't much left over for education, healthcare, daycare, or nursing homes. Although free in other developed countries, these basic needs are beyond reach for millions of Americans.
Terrorism is the new hidden cost of empire building. The US controls an ever larger segment of the world's oil production, but in so doing has incurred the hatred of millions of displaced and impoverished peoples. It was only a matter of time before foreign groups were formed to strike back at our civilian population. Like the gradual erosion of our environment and the lack of funds for basic human services, terrorism is a cost the American public may not have chosen to pay had they been better informed. American corporations have everything to gain by keeping these costs secret and out of the public debate.