It doesn't.

If you read the latest edition of "Atheist Universe" David Mills devotes a chapter to ripping apart the Kalam argument.

There's a good reason for rebutting the premise of a Kalaam argument- it's unsound.

The cosmological argument doesn't directly imply the existence of anyone's particular version of god, sure, but if we just say that and by doing so tacitly accept and agree to the premise of required cause the floor is open to any number of new arguments built on that agreement.

So for example I could say -

Kalaam argument (uncontroversial) necessitates a casual entity.. 

... and this entity is a, b, c, d

therefore it's my God.

This argument can take any form, each of them demanding of pretty much equal respect and time from the philosopher because they are based on a premise that is generically accepted as true or we can investigate the premise of all forms of this argument, ascertain that it's not acceptable and summarily dismiss any argument based on it.

So basically what I am saying is that if the premise of cosmological arguments was a sound one, it would obligate us, somewhat, to take seriously every possible argument for God based upon it!   fortunately, there is good reason to dismiss it, thanks to those philosophers who have taken the time to thoroughly rebut.

What if one doesn't accept thge basic premise... that everything 'began' to exist. I have a lot less problem with an infinately old universe (in some form) than an infinately old intellegence.

LC >;-}>

The argument continues to the type of cause needed to create the universe. Craig, for instance, says that there are only two possible (or likely possible) causes that possibly meet the criteria of timelessness (and so on) and those are abstractions and minds. Abstractions do not possess causal power and so they are negated and thus we have concluded that it the cause of the universe is a mind.  This does no justice to the depth of his argument but I hope you get the gist of it.

You're correct that even if such an argument is correct, then Christian theism remains unproven. Yet, that was never the intended scope of the Kalam argument.

Anyway, it wouldn't make sense to assert that minds are atemporal and that such a mind has causal powers which are responsible for the cause of the universe.

The first problem is the most obvious. The conclusion of universal causality is based on an observational premise that relates to how things interact in the context of time. The denial of the criterion of temporality is in effect, a denial of causal powers. The very idea of causal powers is based upon our observations of the physical world and the manner in which things interact in the context of time (in other words, asserting that an atemporal thing is the causal basis for the existence of the physical universe is a stolen concept fallacy).

The second problem is less obvious but no less grave. If we assert that minds meet the criterion of atemporality, then we are denying their temporal causal powers. It is ultimately incoherent to assert that a mind is the result of some sort of atemporal realm which mananges somehow to interact with the temporal and spatial physical world in the form of mental causality, given that mental events can cause physical events, and we would remain with the problem of the manner in which this atemporal metaphysical entity managed to interact with our physical neural machinery that is the basis of our cognitive capacity. We would furthermore be hard pressed to explain precisely how such things as mental processes occur when the very concept upon which this is based (ie a process) is dependant upon the notion of temporal causality. It seems that because the notions of causality and temporality are so ubiquitous, asserting properties about some sort of atemporal thing will invariably lead to a stolen concept fallacy.

 Funny thing about the cosmological argument..  it originates with Aristotle, whose reasoning was something like:

Every effect has a cause, and a cause is an effect of a prior cause, therefore we can follow this chain back to a Prime Mover.  

Aquinas stole all of Aristotle's stuff, replaced 'prime whosywhazit' with 'God' and called it a day.  Though, despite many people's opinion to the contrary, he had some credibility and cited his source.  He also expressed regret that despite the cleverness of his arguments, none seemed to work.  It's sometimes said that Aquinas died for his philosophy, meloncholy that he never achieved his one goal: to prove god.  (by sometimes I mean I heard  professor mumble it once.)

 He abruptly ceased writing and dictating his masterpiece in part three at question ninety, on penance.  When pressed by his confessor to explain his indolence, he replied, "I cannot, because everything I have written seems to me to be chaffy, in respect to those things I have seen and have been revealed to me."

I stole that quote from here after a quick googling of it.  It's been a long time since I studied Aquinas, so I will rest on the argument that I skimmed there.  I would recommend actually emailing the author (or another academic of medival philosophy) to get more poignant commentary.   I've discovered experts seem to appreciate being tapped for knowledge

I would also point out that using an admission of regret or guilt by the author does not refute the original argument, unless that admission is itself a refutation of their own argument.  If that were so then deathbed conversions of atheists would be appropriate fodder in arguments against atheism, which is clearly not the case.

If you find yourself in the happy circumstance of debating Aquinas' proofs of God, there are plenty of references out there for it.  I believe Aquinas' best proof is the teleological argument, which is clearly wrong.

word to your moms, I come to drop bombs...