According to reports about
a new David Sanger book on the current White House's foreign policy, then Secretary of Defense Bob Gates, frustrated with the Administration's initial revelations of details of the Bin Laden raid, told colleagues, “‘I have a new strategic communications approach to recommend." His plan? "Shut the f@*k up."
Secretary Gates' comments likely reflected concerns about the release of confidential information that could jeopardize participants in the raid, future operations, and relationships with foreign nations. Although given in a substantially different context than a criminal case, the goal, damage control, is the same - not to give away information that can be used against you later in exchange for short term, and probably illusory, gain.
This is what lawyers have been telling people suspected of or accused of crimes in the English-speaking world for centuries.
The best explanation of why invoking and exercising the 5th Amendment rigth against self-incrimination is sound advice that I've ever heard was given by Professor James Duane of Regent University Law School in a lecture captured on youtube (transcript
here). As noted by the professor, Justice Jackson of the U.S. Supreme Court once wrote, *"[A]ny lawyer worth his salt will tell the suspect in no uncertain terms to make no statement to the police under any circumstances." Watts v. Indiana, 338 U.S. 49, 59 (1949) (concurring opinion)."
When police officers warn suspects that anything they say can and will be used against them in a court of law, they're not telling suspects that because they want to. They're doing it because they have to. And they mean it.