Investors worry about insufficient liquidity of their investments. Airports worry about too much liquidity. Anyone who travels by air has encountered and probably been frustrated by the liquid carry-on restrictions introduced in 2006. 3-1-1 is the catchy name that sounds like a phone number but is actually the carry-on limit for air passengers as devised in the USA and implemented worldwide. The 3 stands for the maximum of 3 ounces of liquid (or anything that is remotely like liquid). That is 3 ounces except in countries using the metric system where it is 100 ml or 3.4 ounces. Do metric bombs need more explosive to work?
The 1-1 part of the formula refers to 1 zip lock bag and 1 carry-on case/handbag etc.
For those who like to understand and delve a bit deeper into the liquids issue and airport security in general, check out the official US government website of the agency in charge the Transportation Security Administration. The TSA also runs its official blog called Evolution of Security, which is rather more interesting since it allows people to take potshots at their policies. It seems that is just a ploy to find the weak points in their systems, which is actually a smart thing to do. The TSA calls this facilitating an on-going dialogue.
Renowned security specialist Bruce Schneier publishes his comments on his excellent blog (see the Oct.29, 2008 post titled TSA news with links to a hilarious Atlantic Monthly article describing his all-too-easy circumvention of airport security rules). Scheier's blog is also good for issues of identity theft.
A bit of good news is that the TSA plans to start relaxing liquid restrictions in the fall of 2009 when it begins deploying technology that can distinguish water from explosives.
BTW, is there some secret agreement or pact of honour between western governments and terrorists that only airports and airlines should be targets of attacks? Any crowded shopping district street or mall contains far more people than does any airplane.