Leftists tend to abuse conservatives rather than argue with them and that is so in Australia as elsewhere. Former Leftist Prime Minister Paul Keating is greatly noted for his talent at abuse and his recent comparison of conservative Prime Minister John Howard with Hitler is entirely in keeping with that.
His comparison was, however, a cautious one -- much more qualified and well-informed than the Bush=Hitler mantra that is so common on the American Left. Keating drew a distinction between patriotism (good) and nationalism (snarl) and said that the one thing which Howard and Hitler had in common was nationalism.
The distinction between nationalism and patriotism is an old one -- and the distinction Keating made (nationalism is bad, patriotism is good) dates back at least to the work of Marxist theoretician Theodor Adorno and his co-authors in 1950. Prior to WWII nationalism was good too. There were few more fervent German nationalists than Friedrich Engels (co-author with Karl Marx of Das Kapital).
The debate over what constitutes patriotism and what constitutes nationalism is however an arid one. Keating has his version of it but there are many others. There is an article here that explores some of the other possibilities. The only consistency these days is that if you don't like it you call it nationalism and if you do you call it patriotism.
I myself have had a great deal published in the academic literature on the subject (e.g. here and here and here) but think it is a waste of time to debate what the objective distinction between the two words should be. One has to look at detailed policies rather than use such broad and tendentious generalizations. And I know of none of Hitler's policies that are also policies of John Howard.
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