powers, and the big economies can't agree on anything, then the world as a whole is going to have a hard time as well. so, it's going to be a challenge. and as i said, with a changing world, a rapidly changing world, unity at this point, and in confronting challenges is going to be difficult. >> yeah, but the u.s. may agree to something, but the question is whether they will stick with it, kevin. i'll ask you how does biden convince the world then that, you know from the u.s. perspective, our word is our bond. and it won't be broken by whoever controls the levers of power next? >> reporter: yeah, it's very difficult, you talk about the iran nuclear deals and the paris climate accord, those are all things that the former president withdrew from that this president wants to get back in. there's no guarantee that the next president, whether it's donald trump or another republican won't just scrap the whole thing again and we are