The British Mediterranean Fleet will tip the balance, but when the British bring everything else, things will get really bad for the Italians really fast. And they don't particularly *need* to keep much of the fleet outside Med.
I'm presuming that if there is a war between the Mediterranean Accord and the British/French (etc.) then Brazil is likely to stay out rather than fight the Portuguese. But that doesn't really affect the overall statement.
Absolutelty!
The Regia Marina, while powerful in the Mediterranean, has little in the way of capability to project force outside of the Med. Even closing off the Mediterranean wouldn't be worthwhile- the RN can force it open on the western end, and with IJN assistance, keep the Aden end of Suez open as well, while still allowing Britain to attend to her ongoing overseas concerns.
Although not as clever as
@Sorairo 's Mussolini, TTL Benny the Moose is at least smart enough to not go around picking fights to the extent that OTL's did. While Japan, the USA and Brazil don't exactly have much in the way of fondness for him, nor do Britain and France, none of them have any quarrel with him either, or at least enough of one to bother getting involved.
All of Italy's colonies are close by, unlike the world-spanning British Empire, so it's not as important for Italy's fleet to have the long range that the Royal Navy and particularly the USN's ships have. Still, the
Zara and
Bolsano class heavy cruisers are not to be trifled with- although lightly armoured, they are fast and powerfully armed heavy cruisers. The Regia Marina's submarine forces also provide depth (pun intended) to Italy's defences.
The RM also lacks carriers or even one under development. This is in contrast to France. Although France only had
Béarn, she is now set to take delivery of the escort carrier
Maréchal Pétain, and in late 1942, the light carrier
Raoul Lufberry, both built in the USA. Prior to the war, the Marine Nationale was planning the two-ship
Joffre Class of carriers, the former blown up on the ways as the Nazi invasion closed in.
@Rufus Shinra
Now we're talking
. That's one of the many potential development paths that may be explored TTL. There is a strong case for such a fleet, especially since the RN and IJN have had both of their big victories (Norway 1940 and Tiger 1941) with combined fleets of carriers and battleships. In the former, the battleships were the stars of the show (sinking
Scharnhorst and
Hipper, damaging
Gneisenau) with the carriers providing the supporting role (finding the Ugly Twins, damaging
Hipper and forcing her into port), whereas in Tiger, land-based and especially carrier aircraft shattered the
Kriegsmarine's surface fleet.
Such a fleet, post Operation Tiger, is the very symbol of force projection now, so even its presence now provides strategic deterrent capability. A nuclear-capable fleet of similar description would only amplify this effect.