30-byes near other countries' air space. no surprise that western heads of state were no-shows to his huge world war ii victory day parade this month. but what to do about russia remains the conundrum for nato allies. sanctions are wrecking its economy but not changing its behavior. lethal aid to ukraine is still being considered supported by some of president obama's closest advisers. but the vice president would say only this today -- >> that's a debate worth having and continues. my views are somewhat known on that. but more is needed to be done. >> reporter: he made those comments today a the brookings institute. you might remember it was that think tank and others including former administration officials, who recommended back in february that the u.s. and nato should arm ukraine to deter further violence. they said that this was the gravest threat to european security in more than 30 years and said "the west has the