By the way, the nature of the fundamental forces is actually one of the big areas of research in physics. They know that it needs explaining and try to find why constants have their exact value, why symmetry between forces broke down leading to stars and life
Metaphysical thinking brackets every thing as a whole as needing explanation till you get to something that obviously explains itself, so you would have to ask what the forces are, or more precisely, what the ultimate source of all phenomena is, such that there was a state of symmetry between proposed unobservable things that mathematically could have unfolded as the universe we experience. Hence, from this perspective, all such questions in physics are not "explanation," but only "description," falling short of an explanation that totally satisfies Reason.
Moreover, nobody knows what science is, nobody knows what theories are, nobody knows what kind of knowledge relates to reality and what doesn't. No one even knows if there are laws of nature, what can cause what, or what depends on what, or what substance is, or even if we ought to trust anything but our direct experience with all its content and common sense because it's really all we undoubtedly have. There is a popular conception that science is a well-defined thing, but the truth is, nobody knows what scientific methods are effectual and which are not, and there's thousands of mutually exclusive ways of looking at it. The newspapers tell us that science is just the assumption of materialism, but that is no less a metaphysical view than the notion that the whole universe is in the mind. Both rely on models of unobservable phenomena. Nobody even knows whether scientific models are legitimate science in the first place. There has been a silent civil war raging for several decades between those who think science should be the study of all the relationships between directly observable phenomena alone (the orthodox empiricists), and those who think it proper to propose and study models of unobservables like atoms, subatomic realities, space-time, or laws of nature (the pop physicists like Einstein, Feynman, Hawking, etc), and connecting those hypothetical models with mathematics, forming cosmologies (Big Bang, Dark Matter, Black Holes, Quantum Physics...).
But many scientists don't like the idea of using scientific methods on purely mathematical models of unobservable phenomena because they believe that to be metaphysics and not physics at all. Empiricists have long accused the pop physicists of dealing with imaginary things, proving only what would be the case if such and such a model were true, rather than focusing on relationships between directly observable phenomena. And, in truth, technoscience relies only on observable phenomena. So, there is a very real question as to the usefulness of theoretical physics and whether it is even scientific at all, or rather a metaphysical explication of a materialist model supported by mathematical relationships that may have nothing to do with reality, as none of this work (for example, quantum mechanics) uniquely demonstrates anything useful for prediction or the development of new technology. They are very sensitive about this, so they started this memetic pseudo-war against theism to keep the journalists away from the realist/anti-realist scientific crisis. It's all quite fascinating, if you look into it, since the popular confidence in the myth of a "Science" that is a magic method for knowing is almost entirely false, and it's like a big secret that everyone just pretends isn't so. There's too much money, power, and glory involved.
http://plato.stanford.edu/entries/scientific-realism/#UndTheDat
http://plato.stanford.edu/entries/constructive-empiricism/
The sad fact is, nobody knows anything with certainty. Not even a little bit. There aren't even any degrees of knowledge. Nobody is enlightened at all, and there's not a thing anyone can do about it. It's all just phenomena and faith.