If the US dollar collapses today, many currencies are tied in with it, thus would fail or partially fall with the dollar. I think the Canadian dollar is not as tightly bound to the US dollar as compared to the Yen or The British Pound.

There may actually be a lot less trade between Canada and the USA than between Japan and the US or the UK and the US. Canadians raise most of their food, the UK imports most of its own, and Japan's manufacture relies heavily on US consumerism.

The only reason why the US Dollar is the 'acceptable' medium of exchange on a global scale is because the Dollar remained stable for so long through the confidence it carries.

Many countries are pushing to move away from the Global US dollar, seeking to replace it with something else.

The Euro became a major problem to US banks, its swift adoption and then swift rise in the European market and its 'worth' against the US dollar started the devaluation war between the two currencies.

If china carries through with its threat to switch to the Euro, the strength of the US dollar drops, if enough nations switch from the USD to the Euro - suddenly the Dollar is 'worthless' and the Euro becomes the global standard that all other currencies are valued against.

Technically the USD has collapsed, thus the hyper inflation of the past few years for nearly everyone who has a currency 'backed' or 'valued against' the USD.

Those places that have seen the less inflation, are not as strictly bound to the USD and would suffer less than those nations that are.