The role of Zhukov in this infamous offensive is also a debated topic. American military historian, Colonel David M. Glantz claimed that G. K. Zhukov had to take the main responsibility in the tactical failure of this operation, and this is "the greatest defeat of Marshal Zhukov". In more detail, David Glantz asserted that Zhukov's command in this offensive was not careful, too ambitious, too clumsy and all these lead to a disaster. However, Antony Beevor disagreed with Glantz's comment. According to Beevor, at that time Zhukov had to concentrate on Operation Uranus at Stalingrad battlefield hence he had little time to care about what was happening at Rzhev, which is questionable considering that Operation Uranus was planned by Andrei Yeremenko and Andrei Vasilevsky, and Zhukov played little to no part in it.