"The Salisbury attack is something we got wrong. When it happened, I thought, "Well, probably there’s Russians behind this, because of the use of novichok." I just thought it was Russian gangsters — some business interests, and so forth. I didn't think the Russian state was behind it. And we were wrong. The evidence that's emerged since is overwhelming. We misread that. I still think that the line Jeremy was trying to follow, which is, "Get the evidence first and then state sanctions, and so on, rather than the other way around," is a defensible position. You don't run into saying "This is Putin’s responsibility" when you haven't produced the evidence of it. In fact, this evidence has now been produced. Had we known then what we know now, we'd have taken a different view, I think. We just didn't think the Russian state would be so stupid and brazen as to do something like that — to carry out a poisoning attack on British soil. I know, given the Litvinenko precedent perhaps we should have done but that never really got sorted out so clearly . . . Up until then we'd still ha[d] a quiescent PLP. We were doing all right in the polls. That started bringing all the doubts about Jeremy and the leader’s office to the surface again."