Some anti-Russian propagandists say he means classic liberalism but in fact he himself is a libertarian and so are most of the Russian middle class.
He also says about real things behind that term he uses so it is not really hard to figure out which liberalism he means.
I don’t remember if classic liberalism was about sanctuary cities LGBT dictatorship.
Putin is not a libertarian, he is a throwback tyrant. His opposition to "liberalism" arises because he instinctively sees liberalism as a threat to his autocratic position and as a road to national weakness.
That does not mean that he cannot be dealt with or that he will not participate in deals. It is vital that the American longtime national security objective of preventing Germany, Russia and China from uniting against the rest of the world continue to be pressed. We already see that Putin will play America off by cozying up to China and Germany. Angela Merkel is all too eager to slip between the sheets with Russia. Additionally, Russia has entirely too many tentacles into the Middle East which fit neatly with its central geographical position.
A waning economy dependent too much on minerals and petroleum, Russia nevertheless remains an important player and Trump is right to see the broad geopolitical interests of the United States and he is right, therefore, to romance Putin.