How to analyze the trope "because NOUN" grammatically

Question

In recent years it has become something of a trope to respond to a question with the stark reply "because noun". For example,

Q. Why can't we burn fossil fuels indefinitely?
A. Because science. [Short for something like "because science has shown this leads to catastrophic climate change.]

or

Q. Why can't I just skip class today?
A. Because grades. [Short for "because your grades will suffer" or something like that.]

The appeal of this kind of answer, I think, apart from its current fashionableness, is that the grammatical awkwardness forces the questioner to think harder about what you just said. Its brutal simplicity is at once an admonition ("I'm going to explain it to you in one word, because that's all your question deserves") and a statement of finality. The response may be argued and elaborated upon, but in the end it will arrive at the same point.

We were discussing this in chat today, and I feel that the noun in that construction is deliberately ungrammatical, done for effect. But exactly how is it ungrammatical? One-noun answers can be perfectly grammatical:

Q. What did you order for breakfast?
A. Eggs.

Q. Where did you go to college?
A. Columbia.

Parts of these responses are not really even missing. Complete statements with subject and predicate would appear not to be required.

However, in the "because noun" construction, it feels as if there is a missing predicate; because seems to demand one, and it's not easy (at least for me) to see why that should be so. That's certainly part of the appeal, because without that sense of ungrammaticality the shock value of the trope would be lessened or abated. But why does the noun feel fine all by itself yet incomplete with the addition of the conjunction because? Do conjunctions always require predicates, even if they are elided? Can this construction be analyzed grammatically in some other way than that it is missing a predicate?

Note: I'm looking for an analysis of the grammar here, not a discussion of the difference between "because noun" and "because of noun."

Answer 1

By request, an elaboration of my comments above.

Because has usually been treated as a subordinating conjunction. It can introduce tensed clauses of all kinds, indicating that they are involved in some way prior to some phenomenon or event.

• He went because I asked him to.
• We bought it because what else were we going to do?

Like many such conjunctions, it can be used to introduce a noun phrase (thus making it a preposition), but up until recently, when because was used as a preposition, an auxiliary preposition of was required, unlike other conjunctions like after or before, which don't require auxiliaries to be used when they have an NP object.

• I went because my job requires me to. ~ I went because of my job. (of required)
• I left before they had the accident. ~ I left before the accident. (of ungrammatical)

But recently people have taken to dropping the auxiliary of with because, though not with other conjunctions that take of as prepositions, like in spite, but only in some contexts:

• This seems extremely unlikely, because physics.
• *I had to go, because my job.

Because seems to be in the process of changing from a requisite conjunction to an optional preposition. As usual, this involves different people trying out different constructions at different times and in different contexts to hear how they like it. Enough people now appear to be liking it that official notice has been taken. Because was the 2013 Word of the Year, as determined by the American Dialect Society and the Linguistic Society of America at their annual meeting.

Answer 2

We can see how idiomatic the following are:

1A: “Why do I have to do this?”

B: “Because if you don’t, the end will fall off"

B(i) “Because the boss told you to.”

B(ii) “Because when the iron gets hot, it expands.”

B(iii) Because that is the way it has always been done."

The above actually give an answer but a variation developed on this theme:

2A: “Why do I have to do this?”

B: “Because of the end.”

B(i) “Because of the boss.”

B(ii) “Because of the science.”

B(iii) Because of the tradition"

This is only a partial answer: B will either be able to complete it themselves or ask a further question.

(A further abbreviation of the clause developed on this theme:

In frustration, usually at numerous pointless questions, a common answer became

B(iv) “Because!” which implied “Don’t ask questions, just do it!”)

But B(iv) is a side development, and the original clause has reached the point where the clause has been reduced to “Because” + the essential idea:

3A: “Why do I have to do this?”

B: “Because end.”

B(i) “Because boss.”

B(ii) “Because science.”

B(iii) “Because tradition.”

So the 3B variations are merely a reduced clauses.