As a US citizen by birth; Does flying to France,  surrendering my
passport and joining the French Foreign Legion put me at risk in the
USA for prosecution and
imprisonment?

Hi mercenary and thanks for the question,

In short no, many US citizens have joined the Legion for five years or
signed on for two or more 'contracts' and returned to the US without
prosecution.  In short serving in a foreign army is acceptable unless
that country is at war with the US.

---------------------------------------------------------

"But doesn't serving in a foreign army result in automatic loss of US
citizenship?
No. As explained above, essentially nothing causes automatic loss of
US citizenship any more. If you join a foreign army, you can lose your
US citizenship if you acted with the intent of giving it up.
Otherwise, you can still keep it.

Current US law says that foreign military service will result in loss
of US citizenship if the person served as an officer (commissioned or
non-commissioned) or the foreign military force is engaged in
hostilities against the US; the service was voluntary; and (most
importantly) the person intended to give up his US citizenship.

Current US policy goes further. Unless a dual citizen is serving in a
"policy level position" in a foreign government, commits treason
against the US (e.g., by fighting the US voluntarily during wartime),
or acts in a manner considered totally inconsistent with any possible
intent to keep US citizenship, the State Department is unlikely to
take any action. Further, the current policy statement on foreign
military service recognizes that dual citizens sometimes find
themselves legally obligated to participate in the military forces of
their other country of citizenship, and can do so in such situations
without endangering their US status."
http://www.richw.org/dualcit/faq.html

"Voting in a foreign election, serving in a foreign army, or swearing
allegiance to a foreign government used to be automatic grounds for
losing U.S. citizenship. But a 5-4 decision by the U.S. Supreme Court
in 1967 made it all but impossible for someone to lose U.S.
citizenship unless he or she wants to give it up.

The case involved a naturalized American citizen originally from
Poland, who moved to Israel in 1950. Beys Afroyim tried to get his
U.S. passport renewed in 1960, but the State Department turned him
down. Afroyim had voted in Israeli elections, which meant he had
automatically lost his U.S. citizenship, the department said.

The Supreme Court said the 14th Amendment effectively elevated
citizenship to a constitutional right and ruled that it can be lost
only if renounced."
http://www.usbc.org/info/everything/0502dualcitizens.htm

"The basic point of Afroyim v. Rusk was that the 14th Amendment to
    the US Constitution -- while originally intended mainly to
guarantee
    citizenship to freed Negro slaves and their descendants -- had
    effectively elevated citizenship to the status of a
constitutionally
    protected right.  Hence, Congress had no right to pass a law
saying
    that doing such-and-so would deprive someone of his US citizenship
    against his will.  Specifically, US laws mandating automatic loss
of
    citizenship for voting in a foreign election, working for a
foreign
    government, serving in a foreign army, or even swearing allegiance
    to a foreign country were invalid; said laws =must= provide for
the
    possibility that someone could do one of these things and
neverthe-
    less intend to retain his US citizenship."
http://www.siber.org/sib/visas/usa-immigrant/USandDualCitizenship

"Thus, the court ruled, a section of the Immigration and Nationality
Act mandating automatic loss of citizenship for voting in a foreign
election was invalid. Other, similar provisions providing for loss of
citizenship for serving in a foreign army, or even swearing allegiance
to a foreign country, were similarly invalid unless the action was
accompanied by an intent to give up US citizenship"
http://www.richw.org/dualcit/cases.html

--------------------------------------------------------------

I´m sure you have already read alot of information and given very
serious consideration to what will be expected of you should you
choose to join the Legion, however here are some useful links for you:

French embassy in the USA, Legion website:
http://www.info-france-usa.org/atoz/legion/index.asp

The recruitment process:
http://www.frenchforeignlegion.org/database/data/dta024.asp

Considerable list of information:
http://www.foreignlegionlife.com/

(Also you should note that the C.R.A.P teams of the 2 REP (Commandos
de Recherche et d'Action dans la Profondeur) has now been renamed
G.C.P. (Groupement de Commandos Parachutistes). Whilst the humour of
the CRAP acronym is obvious to native English speakers, trying to
point out the humour to former members is not advised.)

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I hope that answers your question, however if you have any doubts
about my answer do not hesitate to ask for clarification.

Very best regards, and good luck with your decision.

THX1138

Search strategy included:
"serving in a foreign army"
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