BHP always claimed its takeover of Rio was even more compelling in a bad market. Clearly that wasn't the case.

It has just canned its $US66 billion ($103 billion) scrip offer even before it was due to go live in January. Rio shares will tank, BHP will fall, though not as far.

Already the pricing on the deal was skewed in anticipation of BHP chair Don Argus and his board pulling their grand plan for unrivalled global dominance in commodities.

Not having to strap on Rio's $US40 billion in Alcan debt alone is cause for share price celebration on the part of BHP shareholders.

That the European regulators were against the deal on competition grounds and chasing BHP for  divestments in iron ore and coal was a sideshow.

In this dreadful market environment too much debt is a bad thing, a very bad thing.

Rio had already been bringing forward its asset sales program to retire debt. Even three months ago it made more sense for BHP to go it alone. Buying its own shares made more sense.

The impending collapse of credit-starved mining projects around the world will make tasty pickings for any big miner with cash, shares which trade at a premium and a decent balance sheet. This is good news for BHP.

Even the case for merging and forcing through higher prices for the likes of Chinese steel makers lost its glamour once Chinese demand began to ebb.

BHP has capitulated to the inevitable. The costs of implementing such a leviathan global tie-up in a shrinking world economy would have been damaging.

And if the deal really makes sense, BHP can always come back in a few months or a few years.

mwest@fairfax.com.au

BusinessDay