In a pre-drone world you can get explosives, divide them into X equal sized packages, add a timer set to the same point in time to each, then travel around the country hiding them in high-traffic areas.
Yes, that approach is inferior to the drone version. You have to hide them inconspicuously, and a bomb sniffing dog could find them. But you can visit a lot of places in a single European country or US state within one day, and unless the country is already on high alert you can hide something for that time span in public. Yet this doesn't happen. Even regular bombings are rare.
The reasons are manifold: In most places getting explosives isn't actually all that easy (unless you go the homemade route) and is a good method to get attention from authorities. But another factor is that there just doesn't seem to be a large interest in doing that kind of complex attack unless there is already an ongoing civil war. Actual terrorism is fairly rare, and the terrorists tend to be not all that sophisticated.
Are these kinds of drone attacks a scary new possibility? Yes, absolutely! Are they likely to happen? Not really. We might see it as a method to assassinate officials (imagine staging drones at a place where you know the US President will hold a speech in a couple months), but I doubt it will play a major role against the general population
The drone scenario is very different, all you have to do is get close-ish to your target. This is very different than having a stick of c4 sit on your target for months. You have to get them to drone-range, say in the back of a lorry, on a roof somewhere, in a box. Then the programming and or AI can kick in and do the last mile for you, whenever you need. Case in point is the Ukrainian attack on the air fields, they parked a lorry nearby.
Attentive people would find the bombs. Especially if they're on alert, which everyone who knows about terrorism will be at least to some degree.
Back in the day, if you forgot a bag on a British bus the driver would get it and run after you, so that it wouldn't be a bomb issue taking the whole day.
Yes, that approach is inferior to the drone version. You have to hide them inconspicuously, and a bomb sniffing dog could find them. But you can visit a lot of places in a single European country or US state within one day, and unless the country is already on high alert you can hide something for that time span in public. Yet this doesn't happen. Even regular bombings are rare.
The reasons are manifold: In most places getting explosives isn't actually all that easy (unless you go the homemade route) and is a good method to get attention from authorities. But another factor is that there just doesn't seem to be a large interest in doing that kind of complex attack unless there is already an ongoing civil war. Actual terrorism is fairly rare, and the terrorists tend to be not all that sophisticated.
Are these kinds of drone attacks a scary new possibility? Yes, absolutely! Are they likely to happen? Not really. We might see it as a method to assassinate officials (imagine staging drones at a place where you know the US President will hold a speech in a couple months), but I doubt it will play a major role against the general population