It was reported yesterday that the GMB will renew its call to back Britain's nuclear deterrent in order to save defence jobs at Faslane.
A motion for the STUC conference, tabled by the union, declares that working people would be "left to pay the price" of a "political motivated mistake" similar to the loss of coal mines and commercial ship building.
It follows Scottish Labour's decision to oppose the renewal of Trident - a decision which, according to Labour itself, would cost 13,000 jobs in the west of Scotland.
With the SNP also campaigning against Trident, it leaves the Scottish Conservatives as the only party in Scotland which offers 100 per cent backing for renewing our nuclear deterrent - both to preserve Britain's security, and to ensure the west of Scotland economy is protected.
Scottish Conservative leader Ruth Davidson said:
"Labour's in a total mess on Trident.
"Jeremy Corbyn says the submarines could be renewed but the missiles should be left in a shed.
"Meanwhile, Kezia Dugdale says she's against unilateral disarmament, but supports her party's position to sink thousands of jobs on the Clyde by abandoning our nuclear deterrent.
"Labour supporters used to be able to trust their party on this. Now it seems that only the GMB union has got the good sense to stand up for workers and our national security.
"I have met and listened to many traditional Labour supporters who see the common sense in renewing Trident. They are worried about the direction the party is now taking.
"My message to them is that me and my team will stand shoulder to shoulder with you on this issue.
"Together we can make the case for preserving Britain's security, and for protecting thousands of Scottish jobs."