When did laptops become such a danger on planes?

First shoes, then liquids, and now laptops.

With reports suggesting the airplane cabin laptop ban may soon expand from flights originating in eight Middle Eastern and African countries to parts of Europe, it's clear that our computers have now joined the list of things we have to worry about when flying.

However, some big questions remain: Why now, and why are laptops considered OK in a plane's cargo hold but not in its cabin?

Laptops have been a key feature of international travel for years, with passengers in both business and economy classes tapping away on long flights to get work done or pass the time. As the administration of Donald Trump considers forcing certain travelers to check laptops into cargo holds, thus risking cracked screens and possible fires, it is reasonable to ask what's changed — and if this is anything more than security theater.

Unfortunately, the answer is light on specifics.

CNN reported in March that an unspecified al Qaeda affiliate was in fact working to disguise explosives as laptop components. As such, we know that the initial laptop ban wasn't totally out of the blue.

Mashable has since learned that the standard screening process that passengers and carry-on luggage go through may not always be sufficient to detect certain explosives.

What are you doing with your laptop? Credit: Joe Raedle/Getty Images

Checked baggage, however, passes through a different screening process that is able to pick up the explosives. So, the logic is that it's not about separating a would-be attacker from his or her computer as much as it's applying an extra level of scrutiny to devices brought onto planes.

But why now? Well, that one is tricky. We've learned that, apparently, a more thorough assessment of the current terrorist threat landscape led officials to believe that such an attack could emanate out of Europe.

So there you have it. Explosives can be hidden in laptops, and people might be doing that (or planning to do that) in Europe with the intent to bring the devices onto airplanes heading to the U.S.

As to whether or not the extension of the laptop ban to certain Europe airports will actually go through? That's still up in the air, but Reuters calls the expansion "likely."

So, you know, maybe consider investing in hardened laptop travel cases — if there are still any left.