Putin used armor (and air and arty and infantry) AFTER the Georgians started shelling Tskhinvali with 152mm SpGH Danas, BM-21 Grad rockets and LAR-160s. Russian peacekeepers were already all over. Russia gained air superiority quickly and the Georgians never shut down the Roki Tunnel. The inexperienced Georgians very foolishly forced Putin’s hand.
Putin’s argument for South Ossetian and Abkhazian independence was identical to that of the US and EU in Kosovo. Putin demanded they apply the identical standards elsewhere.
The situation in Ukraine is completely different.
I probably should have put a /sarc.