Why have the Argentine and Chilean political cultures been different (despite some similarities, including tremendous British economic influence in the 19th and early 20th centuries plus World War I and II neutrality) throughout their history? Did it have to with Chile, compared to Argentina, a) having a smaller population, b) being more geographically isolated, c) receiving many fewer immigrants, d) having proportionally a much larger peasantry, e) having more mineral resources (like copper, nitrates, and silver), f) having an inferiority complex while Argentina has had a superiority complex, and g) receiving a higher proportion of German and British immigrants - known for their initiative and drive - relative to the population?
Plus, was the reason that Chilean elites had interests in manufacturing and finance as well as land (where Argentine elites had interests mostly in land) because of the greater presence of minerals in Chile?
I would say Chile's geographic isolation had a key role. Have a desert in the north and a frozen wasteland to the south tends to place the heart of the populace in the center. That eliminates the problem of regionalism that other countries at the time had. Chile never really had a caudillo problem because of that too. That allowed a more "conservative" regime to have more control by the 1830s and for decades afterward. Argentina was one of the more wealthy colonies, Chile never shined 'til after independence, so less attention was placed on them during the colonial times.
I'm not sure what you mean by an "inferiority complex" though?
I'd say that the key difference was the rise of Peronism in Argentina. He set the basis to the peronista political culture we see today, based on personalities instead of ideologies, and populist rhetorics. Of course, we could always go way back to the past, to Rosas and Sarmiento's time, to find the early seeds of the caudillista political culture in Argentina. But that would ignore the fact that the PAN was able to achieve a party-based (instead of personality based) hegemony for almost 40 years, carrying forth a coherent political project (which we could agree or disagree with) for an extended period of time. Something happened in Argentina during this formative period.
Torcuato di Tella argues that Immigration played a key role in this. In the decades prior to the Década Infame, almost 30% of the population was foreign born, twice the level of the US or Canada. Also, because this people did not naturalize (no citizenship), they had no access to political participation, so for the most part, they recurred to extra-institutional means to exert political influence. Other factor was that the industrial proletariat and the Industrialist belonged to this group, so the 'modern' classes were left out of the political system, that ended being controlled by the land-owning oligarchy and the native population subordinated to it (the PAN). As you would imagine, this eventually translated into political instability. Peron used this situation to his advantage, integrating those excluded sectors within his populist and corporatist formula.