I think we need a new word for the study of colonialism, imperialism and the post-colonial discourses, pro and con. Pro? Who's in favor of it? Well, this is what makes it interesting, these days: there are a lot of former colonial powers out there whose citizens and leaders, in their heart of hearts, still believe that they accomplished something that was ultimately positive, who still believe that their developmental initiatives and their anti-communist (or anti-capitalist) positions were justified by subsequent developments. This is usually -- explicitly or implicitly -- intended to mitigate or cancel out any discussions of political repression, economic exploitation, military atrocities or strategic abandonment. Sometimes it's just good historical sense, but then it usually comes with very careful caveats about not canceling out the other stuff.
In the former category, we have Japan's second-best known conservative speaking out
[Japanese Foreign Minister Taro] Aso said that ''thanks to the significant improvement in educational standards and literacy'' during Japan's colonial rule, ''Taiwan is now a country with a very high education level and keeps up with the current era.'' ''This is something I was told by an important figure in Taiwan and all the elderly people knew about it,'' he said, according to Kyodo News. ''That was a time when I felt that, as expected, our predecessors did a good thing.''
There's been real research done on things like education and colonial legacies, but Aso is basing his conclusions on "something I was told" and a somewhat panglossian view of early 20th century Japanese leaders. Aso is not trying to present a nuanced historical revision; he's something of a flamethower, politically speaking. Another in a long line of Japanese politicians who is playing to the home audience; this time, though, unlike some of the '80s and '90s gaffes where foreign press turned off-the-cuff statements into scandals, I'm quite sure that he's counting on foreign reaction to emphasize Japan's international isolation and historical victimhood.
For a more nuanced discussion, though Prasenjit Duara's Japan Focus article condenses down some of his recent scholarship and argues that Manchukuo was a "post-colonial" state because it was formally autonomous instead of being a traditional colony. He calls this "New Imperialism" (though I thought the late 19c "scramble for Africa" and Chinese treaty ports was the "new" imperialism; hint: never name something "new" because it won't be for long), defined as "imperialism without colonialism" practiced by the US and USSR as well as Japan in the early 20th century. Some of the hallmarks of New Imperialism are the lack of colonial integration, the use of anti-imperialist rhetorical justifications, and the use of some kind of theory of solidarity binding formally autonomous states together into a community of strategic interest.
It's not a bad definition, but Manchukuo, it seems to me, is a weak example and highlights the difficulty of defining "autonomous" and "state" in meaningful ways. But Duara tries to make a case for Manchukuo as a pretty solidly modern (in concept, anyway) nation-state, and as such a sign that Japanese imperialism produced a modernization effect. Duara is not, in any way, whitewashing aspects of imperialism such as political repression or economic exploitation, but rather pointing out that the instrumental nature of imperialism often required that the imperial subject state be developed -- institutionally and economically -- to the point of being useful to its dominating power. This strikes me as interesting, but not terribly different from World Systems Theory concepts of peripheries and development under dependency.
There's lots of places where Duara's argument doesn't entirely ring true to me. To take one example, he cites Manchukuo's creation as an independent state instead of a colony as a result of intellectual trends and imperialist theories within Japan and the rhetorical structure (Confucian) of pan-Asianism, and seems to ignore the tactical issue: Japan was trying, initially, to get the world to ignore the fact that Manchukuo was a colony, however formally administered. It's interesting to see how the rhetoric fits the situation, but I'm not convinced that the rhetoric shaped the situation so much as the reverse.
Duara is also arguing for an historiographical continuity between pre-WWII and post-WWII imperial networks, which certainly rings true, at least to my World Systems Theory influenced view of imperialism. I never thought that the distinction between "colony", "puppet regime", "client state", and "peripheral economy" was clear lines or, for that matter, all that important in tracing influence; it's the direction and scale of power, which is a continuum, that matters, and the distinction between Imperialism With Colonialism and Imperialism Without Colonialism doesn't really seem all that important to me if there isn't a real difference in effect.