It is an interpretation of the evidence found in the observable universe.
*In interpreting evidence, there are three types of causes used by scientists. 1. Law, 2. chance, and 3. intention (or design).
1. Law explains things like the rate of speed an apple will fall to the earth if dropped from 40 feet. Chance and intention to do not enter in.
2. Chance explains the number of dots that will appear face up if a pair of dice are thrown 38 times in a row. Law and intention do not enter in.
3. Intention explains things like a dead man, lying in a forest with three bullet wounds in the head. Law and chance do not enter in.
The conclusion of intelligent design is simply this: the order of the cosmos (small and large) is best explained by this third kind of cause, namely, it is probably the result of some intelligence acting willfully towards a desired end.
All forms of science draw from each of these explanatory causes, but for the sake of context, I've provided a brief list of sciences that depend heavily on one of these three.
Branches of study relying on Law: Mathematics, Physics (somewhat), Philosophy (somewhat), etc. Branches of study relying on Chance: Mathematics, Economics, etc. Branches of study relying on Design: Forensic Science, Psychology, Literature, Archeology, History, Criminology, etc.
The argument is simply that Physics is one of those sciences wherein intentionality is discovered as a cause. There need be no fear of an unthinking acceptance of any one or the other religious system as a part of acknowledging what is currently the best, most likely hypothesis available for explaining what we see.