Guns in Aircrafts are not Roses

Whenever I look around, I find governments taking 2 different stands on similar issues, but in different contexts.  Here is one more instance of contradictory policies.  The US government does not advice the use a gun in space station or the space shuttle, but the same powers that be is going to insist that the pilots of all airplanes flying into their territory to carry guns.

Apart from this hypocrisy, I don't know whether I am the one with 'crazy brain', but -
We all want the airplane in which we travel to be a totally secure environment, without weapons of any type, so that potential for harm is minimized.  Why would anyone want to violate that environment, by deliberately introducing a weapon, thus spoiling the sterility?

So, now, a malicious person, instead of thinking out ways to get a weapon 'into' the aircraft, is given all the time to think out ways to get 'at' the weapon, already 'inside' an aircraft.  Sheesh, talk of convoluted thinking!

Or is it me who has convoluted thoughts?

But if so, why is the CNN report ‘NASA's plan for unstable astronauts: Duct tape, tranquilizers’
POSTED: 4:03 p.m. EST, February 23, 2007, should be saying this:
NASA has a plan for dealing with a mentally unstable astronaut in space.  Instructions:

• Bind the astronaut's wrists and ankles and tie them down
• Inject the out-of-control astronaut with tranquilizers if necessary
• A gun would not be used; a bullet could pierce a spaceship and kill everyone

If a gun is not good (or rather bad) enough in a spaceship, why is it not so in a pressurised passenger aircraft?

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