As Americans begin to concern themselves with potentially higher tax levies, we suddenly discover that we're not living in a world of our own. It now appears that Australia's Prime Minister Kevin Rudd, who is in a contest for re-election, would love to slap a 40% tax, the Resource Super Profit Tax (RSPT), on his nation's big and powerful mining companies.

But members of the industry -- headlined by the two behemoths, BHP Billiton (NYSE: BHP) and Rio Tinto (NYSE: RTP) -- are willing to fight tooth and nail to avoid the implementation of Rudd's proposal, which he'd have coming on stream in 2012. According to Australia Treasurer Wayne Swan, revenue from the tax would be used to encourage mining exploration via tax breaks and higher pension payments for retirees, among other things.

However, BHP CEO Marius Kloppers has noted that the proposed tax would increase the mining industry's local tax rate from its current 43% to near 57%. At the same time, the higher tax would call into question major projects that have been approved under a completely different set of financial assumptions. That, from my perspective, carries with it implications that are more than a little daunting.

Similarly, acquisitions in the industry that are currently in the works, such as U.S. coal producer Peabody Energy's (NYSE: BTU) $3.8 billion takeover of Australian miner Macarthur Coal, could be put on hold while the companies consider the implications of the proposed tax. Also, other combinations that might have occurred -- I've long thought that BHP might someday develop an appetite for Freeport-McMoRan (NYSE: FCX) -- could become far less likely to see the light of day.

During the past couple of years, the three big iron ore producers -- including Brazil's Vale (NYSE: VALE) -- have battled with the Chinese steelmakers when it came time to set ore prices for the year. Should the RSPT be implemented, it'll be interesting to see if major Australian producers try to pass on the expected cost of the legislation. And then to what extent that will effect Vale's negotiations.

I recognize that many of my Foolish friends might be inclined to jettison their BHP or Rio shares. But I wouldn't act too hastily. These are solid companies, and there's a good chance that China alone will keep us in a secular bull market for commodities for a long time to come.

Fool contributor David Lee Smith doesn't own shares in any of the companies mentioned above. He does, however, welcome your questions or comments. The Motley Fool has a steel-hardened disclosure policy.