At the Nato summit this week, the star attraction was President Zelenskyy of Ukraine. But while he knew he was among friends - and allies were keen to emphasise their continuing support - he came with a clear demand: let Ukraine join the Nato alliance.  But even before his arrival, the mood music suggested that Ukraine was not going to be offered membership to Nato, nor was it going to be given a clear timetable on how and when it could join. With President Erodgan of Turkey also holding up Sweden’s membership, it seemed like Nato had some trouble ahead of the summit. But then things changed. On the eve of the summit, Erdogan said he was stopping his blocking of Sweden’s application, and during the summit, President Zelenskyy appeared to accept that even if membership was not forthcoming, the head of Nato was clear that it might come one day. But how might the war come to an end? And why can’t Ukraine join now, to deter Russia? In today’s episode, we put these questions to Emma Ashford, an expert on Russia and Europe at the foreign affairs think tank, The Stimson Centre. I spoke to her about Nato, the war, and how it might conclude.