Everything has advantages and disadvantages. Many things also have a good side and bad side. As for jammers, even more so, they are both useful and dangerous. This is why many countries are banning the use of different jammers.
Take GPS signal jammers for example, most people use it to combat GPS tracking and protect their privacy. This is our privacy right. However, GPS jammers can also be used to steal cars. Imagine the following scenario - you are driving a car with an integrated GPS system, and you know that even if something unfortunate happens if your vehicle is stolen, you can easily track it with the help of a GPS system. But unfortun