Labour supports the renewal of the Trident submarine system. But any prime minister should be extremely cautious about ordering the use of weapons of mass destruction which would result in the indiscriminate killing of millions of innocent civilians.
This point needs absolute clarification by Corbyn, it's far too important for there to be any doubt. Corbyn is on record as saying he would not authorise the use of nuclear weapons in retaliation, May has given an unequivocal "yes". If Corbyn will not "press the button" (and yes, I know there is no button) then the whole point of it as a deterrent is lost. In those circumstances, better to scrap the whole thing and spend the money elsewhere in defence.