You cannot be simultaneously for and against Trident WMD renewal

I never thought I would agree with US Presidential candidate, Republican Donald Trump, and disagree with a shadow minister in Jeremy Corbyn’s shadow cabinet, but on Monday I did, on nuclear WMDs.
Trump said in the Presidential debate in New York on Monday  “I agree with her [Hillary Clinton] on one thing. The single greatest problem the world has is nuclear armament, nuclear weapons.” (New York Times, 27 September 2016; http://www.nytimes.com/2016/09/27/us/politics/transcript-debate.html)
Meanwhile, Labour shadow defence secretary, Clive Lewis, controversially said at the Labour Party conference on the same day: “I am clear our party has a policy for Trident renewal.”(Labour defence chief accepts nukes policy: CND dismayed at continued Trident support, " Morning Star, September 27; http://www.morningstaronline.co.uk/a-2655-Labour-defence-chief-accepts-nukes-policy#.V-pWN-QVCM8)
Later,  on BBC’s  Newsnight John McDonnell put forward the nonsensical justification that Labour could have a policy in favour of renewing Trident, while he as shadow Chancellor and Jeremy Corbyn as leader, could continue to oppose it.
That is untenable, as the leader of the Labour Party cannot campaign in a general election against something included in his party’s manifesto for the  election.
The issue cannot be “parked" as Lewis and McDonnell have intimated to various media; it has to be decided.
Publishing the review of Trident, security and defence issues, to which many Labour members contributed in good faith in the spring, would be a good start.