This is very simple, so I'm not going to spend a lot of words on it. Reins are [typically] leather straps that attach to a bit and bridle, for the purpose of steering a horse. A reign is a period of rule by a monarch. You can reign in a country, but you cannot reign in a horse. There's not enough room in there. When someone says they want to "reign in" some kind of activity by someone else, or "seizing the reigns of power" they are demonstrating their poor command of the English language and you should stop reading immediately before you get any on you.
One of the most common arguments seen on geek-news discussion forum Slashdot is over the distinction between copyright infringement and theft. Theft, of course, requires depriving someone of something, which is why we have copyright law in the USA and internationally. One of the tools used for this purpose is the repurposing (or "railroading", if you will) of the word "piracy" to apply both to persons who take naval vessels by force of arms and to infringers of copyright. I propose that we stop supporting this deliberate and misleading act by refusing to repeat the terms being used to demonize copyright infringers, and instead using terms that actually mean something.
So I'm putzing around Slashdot, replying to comments, and one of them contains the following tidbit:
Finally, using the word rape is way over the top and trivializes a real problem in society -- I'm sure you didn't mean too, but you can get your point across while toning it down a bit too.
Now, this particular bit outlined a piece of stupidity that we often see here in America. It's called Political Correctness, or "PC", and it's always linked to insufficient mental activity.