neil hilton wrote: ... Having said that Force H at that time was pathetic.
Well from what I saw it didn't even exist on 10 June. Not being formed until later that month I believe.
The RM did have a few BBs, enough to provide escort and fire support for an invasion force.
The problem is the French had a few BBs as well and can probably show up at Gibralter in a day or so even without advanced warning. But if the RM isn't at war I'm sure there are consular agents watching it if war is declared thier activity can be curtailed but that's going to place both the British and French on alert.
Radar at Gib at that time was poor and an invasion could well have sneaked in and achieved surprise.
I believe there were some planes based at Gibralter and I think HMS Argent was their at the time. The British and French aslo have a fairly large combined fleet at Alexandria and there are some British ships at Malta.
There's also the problem of where to land at Gibralter and what to land with/from. Somewhere there's a good list of what defences were there over time. I'll see if I can find it.
has some info on the defences of Gibralter from 1939 through 1941. The 8 9.2" guns would probably constiture a significant threat to the old Italian BBs. Those and the 6" guns would be a serious threat to any landing craft.