The last thing you want to do around a police officer is to act up, act nervous, or freeze. If you have ever been around someone who is acting nervous or suspicious, it probable makes you aware that something is not right and to be a little more vigilant with that person. Police officers are the same way and trained to pick on those clues. The only encounter that I have had with a police officer was a couple of summers ago, I was downtown and asked for directions to the outdoor Red Dress Party.
On occasion I have been asked for ID on entering a night club or while passing through TSA security to catch a flight. Never has been an issue.


					
					
					
					
				
  If you travel abroad much you will know that most countries usually require non-citizens to carry ID (normally their passport) all the time as they would have to be able to prove both their identity and their legal right to be in the country (generally via a visa) if they were challenged by local law enforcement.  I can imagine a lot of US citizens never bothering to understand this about other countries but there are some where you could just end up in clink for a day or so without appropriate ID...  and there are some countries where that wouldn't be pleasant, even in Greater Europe...  
) and possibly in one of the larger cities - more liberal, but with laws similar to those of Germany (China, Malaya, Singapore would all fit this pattern).  The poster is clearly quite used to routine ID checks and the professionalism and courtesy of the police seems quite refreshing bearing in mind the broader reputation of police in some far-flung regions.

						