The path toward rolling out wider use of whole-body security scanners in U.S. airports runs through the White House.

The failed Christmas Day attack aboard a Detroit-bound U.S. airliner has created congressional calls for greater use of body scanners that advocates say would have detected non-metallic items such as the explosives an Islamic militant from Nigeria is accused of smuggling on board.

Dutch authorities said on Wednesday Amsterdam's Schiphol Airport, where the Nigerian suspect made a connection, will begin using full-body scanners within three weeks.

U.S. President Barack Obama could expedite such a deployment because the Department of Homeland Security (DHS) and Transportation Security Administration (TSA) don't need legislation from Congress to start using the devices at any of the 560 U.S. airports with scheduled airline service.

Current use is limited to a 19 airports and is optional -- passengers can choose to undergo a pat-down instead.

A greater U.S. government shift toward using the high-tech devices could create a boom for makers of security imaging products, and it has already created a speculative spike in share prices in some companies.

It would also set off opposition from civil libertarians who consider the body scanners an invasion of privacy that is akin to a strip search -- a claim hotly contested by security advocates. The devices detect objects concealed under clothes and can produce detailed images of the body. Operators in a separate room view images that blur the face and genitalia.

In a pilot program implemented after the September 11 attacks of 2001, TSA operates 40 millimeter wave technology units at 19 airports and has purchased 150 backscatter, low-level X-ray machines that will be deployed over the next year at a cost of $130,000 to $160,000 per unit. In addition, TSA has plans and funding to buy another 300 units in 2010.

Because ceramic knives and explosive powders and liquids can pass through standard metal detectors without setting off alarms, authorities might consider forcing passengers to pass through whole-body imaging machines.

That would be a DHS decision. Clearly we would work with DHS, the White House and our congressional partners on security decisions, TSA spokesman Greg Soule said on Tuesday.

Asked about the Dutch decision on Wednesday, Soule said TSA had no immediate comment.

Congress could get involved. Legislation that would limit full-body imaging to secondary searches passed the U.S. House of Representatives, but has not passed the Senate. But even the co-sponsor of the amendment, Representative Jason Chaffetz, said: I support the machines being widely deployed.

The White House has tip-toed around it, said a congressional aide familiar with security issues who spoke on condition of anonymity. They have invested pennies, basically, in relation to what it's worth. They are trying to be responsive to the ACLU and the people who are some of the bread and butter of the Democratic support network.

ACLU INCREDULOUS

The American Civil Liberties Union (ACLU) says it does not trust the privacy safeguards, saying the images that depict body shapes and private parts would still exist.

If a celebrity goes through a scanner that kind of image could end up on the Internet, said Jay Stanley, an ACLU privacy expert.

We would certainly all be safer on airlines if we all flew naked, he said.

Investors bid up the stocks of imaging companies like American Science and Engineering, OSI Systems, and ICx Technologies Inc between 10 percent and 26 percent on Monday and Tuesday, the first two trading days after the incident.

Shares in the larger and more diversified L-3 Communications Holdings Inc climbed 1.7 percent, while smaller privately held companies like Millivision Technologies are hoping to take advantage of the interest to find sources of venture capital or private equity investment.

Millivision, an 11-employee company based in Massachusetts, says its $180,000 units can operate in privacy mode where the operator sees only a video image that highlights concealed items in red.

I'm comfortable having my wife or children go through the Millivision system, but I would be a little bit concerned about having them go through a system that did not have privacy, said Paul Nicholas, president and CEO of the company.

(Additional reporting by Basil Katz in New York and Kyle Peterson in Chicago; Writing by Daniel Trotta)

Nigeria Barack obama Privacy Security