At one time, Argentina rivaled Canada in terms of wealth. Up until 1930, Argentina grew along the same trajectory as Canada. However, in response to the Depression, Argentina turned inward and instituted disastrous policies, many of them populist, inward-looking, and economically insane, whereas Canada responded to the Depression and its aftermath (and the war) in a far more methodical and competent matter.
Unfortunately, Argentina has never been able to shake its tendency towards populism and, at times, hostility towards international markets. Today, the GDP of Argentina is well below that of Canada.
From the Worthwhile Canadian Initiative blog.