Tailgating on the other hand is always dangerous, is endemic to our roads and is barely ever prosecuted. We hear more about prosecutions for disrespectful reactions to tailgating, than we do about prosecutions for drivers using tons of metal travelling at high speed to intimidate fellow road users and put their lives at risk.

It may be harder to detect than speeding (although as Diego points out, it may not) but focusing on a means to monitor and address tailgating would definitely have a marked effect on the safety of our highways.

Heavy fine should be imposed to tail gaiting. I think the speed radar technology can be also used to detect tail gating or cars not respecting safety distance. speed radars can detect the cars passing by a single point, so the interval between 2 cars can easily determine their distance and the car behind should be heavily fined.
Tail gating is extremely dangerous more than speeding. Slow cars on the left lane should not be a excuse for tailgating or flashing lights. In an ideal world, the left lane should be used only to overtake, but this is not the case in many parts of the world and UAE is not an exception, ultimately tailgating or lights flashing is not a solution for this and it is an instigation for an accident and this must be avoided.

The website of the Department of Motor Vehicles of California includes this helpful suggestion:

To avoid tailgating, use the “three-second rule”: when the vehicle ahead of you passes a certain point such as a sign, count “one-thousand-one, one-thousand-two, one-thousand-three.” Counting these numbers takes approximately three seconds. If you pass the same point before you finish counting, you are following too closely.