I should insert a sort of note to clarify something: The thesis that the rise of the Hittite Empire was enabled by control of ironworking is now generally thoroughly rejected. The argument is based almost entirely on a single letter discussing a shipment of iron as well as various textual references to ironworking, but this does not prove much except that they used iron for things. More importantly, studies of Hittite texts indicate that most references to iron are for small ceremonial objects rather than large military consignments and that the apparent increase in references to iron is largely an artifact of the fact that most of our extant Hittite texts are from late in the Hittite Empire to begin with. It is also eminently unclear how much quality control Hittite ironworkers were able to maintain; scientifically examined iron artifacts from the Hittite period suggest at least a certain amount of mining some essentially useless ores only to find that they could not be usefully forged and that they did not yet understand how to control the carbon content of iron well enough for consistent large-scale production. They did, have a clear understanding both of smelting and forging iron, itself a difficult technical achievement, but it's not at all clear that this was a major factor in their imperial success. More likely important is a combination of external political factors(the collapse of Babylon as a real regional power, the downfall of the Mitanni Empire) and internal political factors(the very flexible succession system, which allowed for more talented younger siblings to claim power over older siblings, and the remarkably ability of the Hittite royal house to survive seemingly catastrophic territorial losses, up to and including the loss of the capital Hattuša itself at various points).