Rick Perry wants to scrap three government departments. What would that mean?

Rick Perry's excruciating brain freeze as he tried to remember which government department he wants to eliminate was clearly the YouTube moment of last night's debate. But lost in the hilarity was the question of what Perry's plan would actually mean.

Perry said he wants to scrap the federal Departments of Commerce, Education, and Energy (even though that last one eluded him for a while). So it's worth asking: What do those departments do?

The Department of Commerce contains the U.S. Patent and Trademark Office, which runs our system of intellectual property. Without it, America would have no way to ensure that inventors could fully profit from their inventions, giving them little incentive to spend the time and money needed for breakthroughs. The pace of American innovation would likely take a huge hit.

Commerce also includes the Census Bureau. The accurate count of Americans that the department provides each decade lets leaders and policymakers know how to allocate resources--housing, roads, utilities--around the country. And Commerce also encompasses the National Weather Service (NWS), which issues crucial warnings about severe weather like hurricanes and floods. When state and local officials make decisions about how and when to evacuate, they're generally going off NWS information.

The Department of Energy, created during the Carter administration, protects U.S. nuclear weapons from accidents or terrorist attacks that could release dangerous radioactive material, killing thousands. Without the oversight that the Energy Department presently provides, it would be difficult to maintain a nuclear weapons program at all. The Energy Department also plays a key role in funding and promoting the civilian use of nuclear power.

As for the Department of Education--likewise created under President Carter--its role is more limited, because the U.S. education system is highly decentralized. Indeed, Perry is hardly the first conservative to pledge to abolish it. The Education Department does have a role in shaping education policy, however, by handing out funds to states that adopt its preferred reforms, and it also enforces privacy and civil rights laws in schools.

Of course, Perry could eliminate the departments but maintain all these functions, by simply shifting them into different agencies. The Pentagon, for instance, might take over management over nuclear weapons. His economic plan, "Cut, Balance, and Grow," doesn't mention his plan to eliminate specific departments. Some agency functions might also devolve to state or local authorities in Perry's plan, but it's hard to see how major initiatives could get funded at the state or local level--particularly in rough economic times like the present. But we'll learn more about Perry's plan next week when he plans to give a speech on "government reform," a Perry spokesman told Yahoo News.

Until then, it's fair to say that doing what Perry recommends would mean either scrapping, or fundamentally reassigning, some key government functions.

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