karat and party can't withdraw support from govt. before end of 2008, after this might happen that they might not get another opportunity to be in centrer and more importantantly keeping the control of govt. karat and party keeps the govt. spinning so that their value is not decreased.
Karat and party know that India has to be with nuke-deal if it wants 10% gdp growth. the problem is not with the deal but with their differences with US. had it been russia the deal would be in operation.
Whole nation knows that its the politics that is going not any negotiations , after all Manmohan Singh is more patriotic than left.