The apparent success of Toyota, Ford and Holden in fighting off foreign competition while increasing their exports has led some to conclude that orthodox trade theory based on the law of comparative advantage might be flawed or inadequate. This led one economic commentator to state that the traditional theory of comparative advantage said that Australia would be hopeless at making cars. The theory never said any such thing. No wonder ordinary folk get confused on economic matters, many even concluding that economics is only a matter of opinion and that protectionists might be right after all.
Most people find the law of comparative advantage very difficult to grasp.
I'll try to explain it without doing it too much violence. The law demonstrates why it pays a country to import certain goods even though it is technically more efficient in their production. Because the factors needed for the production of X in Australia are more highly valued elsewhere. Therefore, using tariffs, for example, to encourage the production of X reduces the production of more valued goods elsewhere in the Australian economy and that lowers the country's total output and thus welfare. By importing X the output of other goods expands and total output rises.