It goes like this:
If someone is a jihadist terrorist, then he is Muslim.
So-and-so is Muslim.
Therefore, so-and-so is a jihadist terrorist.
The problem with this logic is that it is flawed. In philosophy, it is known as affirming the consequent, or an attempt to infer the reverse from the original statement. The deficiency here is the IF clause was never asserted as the only sufficient condition for the THEN clause to be true. While the IF clause may be true, there can also be other factors, unspecified in the original statement, that result in the THEN clause being true. To demonstrate how deeply flawed this type of thinking is, consider the following:
If something is a fish, then it can swim in water.
An otter can swim in water.
Therefore, an otter is a fish.
Faulty logic is lazy logic. It is the hallmark of a lazy intellect, a shallow thinker, and an incurious mind. It reduces complex concepts into simple sound bites. Feeding these to an audience hungry for a scapegoat only whets their appetite for more fallacies to continue justifying their worldview. Unfortunately, this is the type of “truth” that is the currency of the new administration, where all negative news regarding it is deemed “fake news” and they offer “alternative facts” instead. It is only a matter of time until a lot of people get hurt.
Welcome to 1984.