The logic cannot be faulted: Australian miners are generally over-leveraged and strapped for cash. And the world's largest consumer of metals is determined to tighten its grip on global supply after a few nasty years at the mercy of BHP Billiton, Rio Tinto and Vale.

But the concatenation of deals places a lot of pressure on Australian treasurer Wayne Swan, who has the power to approve or reject them. The administration, led by one of a handful of Mandarin-speaking premiers outside Beijing, is instinctively pro-China. Yet among developed economies, Australia and Canada have the toughest foreign investment regimes in the world. Canada, because it is sleeping next to the elephant; Australia, because it owns the resources everyone else wants. The fear is that Australia will end up as a pure supplier nation at the foot of the value chain, having ceded vital technology and know-how.

China, burned by previous failures, recognises the threat of rejection. Fortescue/Valin seems structured as an antidote to Rio/Chinalco, as if presenting Mr Swan with a choice between the two. Where Rio is trumpeting a “Pioneering strategic partnership”, Fortescue's is a more muted “Share Subscription Agreement”. Perhaps China will be happy if one or two proposals slide. But the flurry of deals is a risky strategy, at a time when politicians, egged on by voters, are flirting with economic nationalism. As with pig iron emerging from the furnace, a cooling-off period would be wise.