1) when they know that elections even if UPA loses the trust vote will happen in march and if they win by may. so the 100 crore loss should go for BJP with communists did that.
2) as far as my knowledge is according to Indian constitution the defence of a state is under state govt (BJP in the matter of gujrat and karnataka) and center cannot take part till either it is presedent rule or it is requested from them by state govt. so for bomb blast BJP should be blamed.
3) For cash for vote. if somnath would have deffered does it not means India would have lost another 50-80 crore rupees.
4) if somnath would have regined does it not going against indian constitution
5) well about nuke deal advani has quoted they will accept the same deal if they are in govt but they will oppose it if they are oposition like women's bill