During ‘Round Table Discussion’ (https://www.youtube.com/watch?v=UMEpo6h3A-s ) on March 12, 2022 over Russian invasion of Ukraine, Major General (Retd) G.D. Bakshi said that what has emboldened Prez Putin to challenge the USA to come and fight with Russia on the Ukraine front and the reasons behind  the refusal of the USA and even of Europe / NATO  to put boots on ground in Ukraine is the fact that the USA now knows that it can’t fight Russia in Russia’s back-yard. Because (as per Gen Bakshi) it is not merely the old minor disparity in nukes (6,300 with Russia v/s 5,500 nuclear warheads with the USA) but now with new developments by Russia of ‘Topol intercontinental ballistic missiles’ and Hypersonic-missiles (which can maneuver and goes at 6-7 times speed of sound) the Russian + Chinese technology has defeated the US-technology. Russia is now not listening to the USA because so far the USA had superiority in air power but Russia by manufacturing technologically advanced aircrafts and also by bridging the gap in conventional arms and especially by bringing an anti-missile system (S-400), Russia has finished the air superiority of the USA]”. 

So far the entire mankind is given to understand that the USA is not putting its boots on ground in Ukraine (despite Budapest memorandum) because it will escalate the war and will cause catastrophic nuclear war (which Russia has already threatened formally). But in view of the military equation explained by Gen Bakshi it seems the USA (along with West) is afraid of military defeat by Russia (supported by China) in Ukraine war which seems to be a plausible reason for the dereliction of the USA (about Budapest memorandum) and of the leader of free world and of the ruler of world order, the USA because:-

Mankind has always needed political rulers (even Chanakya / Kotilya in 4th century B.C. mentioned in his famous book ‘Arthshashtra’ that one should not live where there is no king) and will need them in future too. Since the end of World War II, the USA has been the ruler of the world through the UN at US-soil (which created 193 countries and more or less provided them with territorial stability and even comparative peace). Hence when the ruler of the world the USA killed / allowed to be killed many people of other religions [non-Christians like Muslims (in Afghanistan, Iraq, Syria, Libya, Yemen. Palestine etc) and Buddhist etc of pacific countries Vietnam etc] rest of the world didn’t consider it unusual or abnormal for a ruler (the USA) hence kept quiet (notwithstanding minor grumblings about it by the rest of the world). But now when Russia is killing people and that too, Christians in Ukraine then it raises an important question that - ‘now who is the ruler of the world (in this age of globalization)’ ? Moreover no one gives-up the status of rulership unless challenged by some superior  military power. Hence China + Russia already have de-facto proven their superior military power on ground (through Ukraine) than of the West led by the USA and now it is merely a matter of time that it will get reflected de-jure too in various global organizations / treaties etc like the UN, WTO etc.

This does not mean that the USA faces any military threat on its soil from China + Russia combined because the USA is still a formidable military power (even without the support of Europe / NATO) and can easily take care of its (and of its Western allies) external and internal security. But in this emerging situation the problem lies especially to one non-Western country namely India which is foolishly (even in changed global military equations) messing with China through QUAD etc.

Though India keeps on saying that Quad is not anti-China but China considers it 'anti-China on the instigation of the USA' and objects India’s participation in Quad as reported also at https://economictimes.indiatimes.com/news/defence/jaishankar-dismisses-chinas-opposition-to-quad-says-it-will-do-positive-things-contribute-to-prosperity-and-stability-of-indo-pacific/articleshow/89519811.cms?from=mdr . Due to this anger of China against India, China has already taken an aggressive position against India at Eastern Ladakh since 2020 (including by capturing some Indian territory). But at what point China will call it ‘enough is enough’ and will ‘teach’ India a lesson by a major war (as China did in 1962 war) can’t be said with certainty. Moreover it does not make things easier for India especially when Pakistan is already waiting for a nod from China (rather China + Russia combined) to take J&K (and not merely Kashmir) militarily from India.

Therefore, in the given situation when even the USA (along with its Western allies) is afraid of militarily fighting with Russia + China combined on-ground at Ukraine, it will be suicidal on the part of India not to revisit its policies towards China especially those (which instead of relying on international rule-of-law through global organization, the UN etc) militarily irritates China (directly) such as Quad and India’s support to pacific countries which are having martial disputes with China.