It works on more than one level as a joke:
the Falklands war started (as far as the Brits are concerned) with Dravidoff and his team of scrappers raising the flag at Grytviken while they were tearing down the old whale boiling plant there. If they'd not raised the flag, things may have been so much different. They had contracts to remove the metal - and if anything were doing the world an environmental favour. They just raised that flag...
And of course theres the irony (as already pointed out) of towing a rusting collection of scrap metal plates from the Falklands and rebuilding it into SS Great Britain