Why would Putin roll over Ukraine quickly, when he can simply take his time, and let Ukraine bankrupt the United States? Much more effective in the long run.
Pretending this debacle and global humiliation and depletion of their advanced weaponry, Air Forces, missiles and rockets, Armor and artillery pieces, Air Defenses and Navy, political unrest, loss of weapon sales, loss of the cream of his military, and loss of his vast Soviet war material stocks, major increases in NATO membership and geography and readiness, and the loss of European energy sales was the original plan rather than a quick image building display of Russian Army efficiency and modernization, and effectiveness as they swept in and quickly took Kyiv and then all of Ukraine, isn’t effective or credible.