A few weeks ago, a nonpartisan group revealed that the Federal government spends more on immigration enforcement than all other law enforcement combined. Altogether it spends $18 billion a year–most of it to keep people out of the country and prosecute and deport those who get in without documentation.

The United States spends more money on immigration enforcement — nearly $18 billion in the 2012 fiscal year — than on its other law enforcement agencies combined, according to a report released Monday from the nonpartisan Migration Policy Institute.

That spending went to U.S. Immigration and Customs Enforcement, Customs and Border Protection and US-Visit, a program that helps states and localities identify undocumented immigrants.

By contrast, the U.S. spent $14.4 billion — combined — on its other prime law enforcement agencies: the FBI, Secret Service, Drug Enforcement Administration, U.S. Marshal Service and Bureau of Alcohol, Tobacco, Firearms and Explosives.

Today, Janet Napolitano basically told Congress to fuck itself and its demand that all shipping containers bound for the US be screened. Apparently, the one time $16 billion price tag is too much to ensure that our trade cargo undergoes the same scrutiny actual people do.

Homeland Security Secretary Janet Napolitano on Thursday suggested that her department does not plan on meeting a congressional requirement that all foreign cargo shipped to the United States be scanned for dangerous materials that could be used in a terrorism attack.

Congress in 2007 approved a law that requires all ship cargo bound for the United States be screened for weapon-usable nuclear and radioactive materials and other dangerous substances before the vessels sails away from foreign seaports. After missing an initial deadline last July to come into compliance with the law, the Homeland Security Department now has until July 2014 to meet the mandate.

“I actually looked into this issue very thoroughly,” Napolitano said during a Wilson Center event here.

Last spring, Napolitano told lawmakers it would cost $16 billion to deploy screening technology at all of the approximately 700 international seaports that send cargo to the United States.

“It’s one of those things where as we have grown and become more knowledgeable about how to really manage risk, we have recognized that mandates like that sound very good but in point of fact are extraordinarily expensive and that there are better and more efficient ways to accomplish the same result,” Napolitano said on Thursday.

Mind you, what shipping container screening is being done is largely included in that $18 billion a year figure, which includes Customs and Border Patrol’s budget of $3.5 billion. So fulfilling the Congressional mandate would only inflate the larger number.

Moreover, I’m willing to entertain the notion that it doesn’t make sense to scan each and every shipping container.

You know? In the same way it simply doesn’t make sense to make each and every airplane passenger take off her shoes and go through a backscatter machine?

But the disparity in what DHS is willing to spend to keep people out of the country as compared to what it is willing to spend to keep contraband trade and weapons out is telling.

It makes it clear, first of all, that DHS doesn’t believe it has to fulfill every Congressional mandate, including the one that mandates DHS round up 400,000 people a year to deport. I’m not saying I agree with that; I’m noting that DHS chooses when to follow the requirements Congress sets.

It also makes clear that importers would never be asked to undergo the same inconvenience and cost that actual people do (ultimately, importers should be paying the cost to ensure their shipping containers are safe, not taxpayers).

It appears, then, DHS is far more interested in keeping undocumented people–whether they present a risk to the US or not–out of this country than it is keep contraband trade out.