all means, whether putin is attempting to set up a distraction or whether he, in fact, is seeking an invasion of ukraine sometime next year. administration officials have said that if putin tries it, there could be a whole round of financial sanctions to make putin pay. joe johns, cnn, the white house. joining me now with her perspective is natasha linstadt, professor of ethics. >> thank you for having me. >> in president biden's call with russian president putin over the tensions triggered by russian troops massing at ukraine's border, mr. biden already accepted he won't accept red lines set by moscow. how careful does he need to be? >> he does need to be very careful because what russia wants is for very clear