Why do I have to take my laptop out of the bag at airport security?

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CNN
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Anyone who has traveled by air in the past 10 years will know how stressful airports can be.

You didn’t leave home as early as you should have. In the mad rush to get to your gate, the security screening seems to slow everything down. And to add insult to injury, you’re met with the finicky request: “Laptops out of bags, please”.

But what does your laptop have to do with security?

Airport security changed dramatically after the terrorist attacks in the US on September 11, 2001. Before 9/11, you could pass through security with a carry-on bag full of everything you might need for your vacation, including a knife with a four-inch blade. Indeed, that’s how the 9/11 attackers brought their weapons on board.

After 9/11, screening processes around the world changed overnight. In the US, private security contractors being paid a minimum wage were swapped out for a federalized program with highly trained security personnel. Anything that could be considered a weapon was confiscated.

Around the world, travelers were suddenly required to remove their shoes, belts and outerwear, and take out their phones, laptops, liquids and anything else that could be used as part of an improvised explosive device.

This lasted for several years. Eventually, more advanced screening methods were developed to effectively identify certain threats. Today, some countries don’t require you to remove your shoes when passing through security.

So why must you still take your laptop out?

The machine your bags and devices pass through is an X-ray machine.

The main reason you have to remove your laptop from your bag is because its battery and other mechanical components are too…