Canada and Australia, hitherto the beacons of the global economy, could be finding themselves in a pickle.

Slowing global growth is threatening their export sectors. As their economies slow, their currencies will weaken, pushing up imported inflation. And then there's the small matter of domestic bubbles.

Despite their reputations as major exporters, both Canada and Australia have been running large current account deficits. The IMF forecasts Australia's deficit to breach 4% of GDP this year and to hit 5.5% next. Canada's is seen at 3.4% this year and 3.7% next.

Now, of course there are two sides to these deficits. They equally reflect foreigners' desire to invest in these countries (a capital account surplus) as domestic residents' desire for imports. But imbalances of these sizes are worrying. Until 2009, Canada spent more than the previous decade with surpluses or modest deficits. Australia has consistently run large deficits from at least 1980, though rarely of the 6%-plus range it's expected to hit in 2014.

If Chinese demand for industrial commodities has peaked and Chinese speculators are forced to de-stock because of tightening credit conditions, prices of these commodities will not only fall, but they'll collapse, argues Michael Pettis, professor of finance at Peking University.