Germany had the Prussian influence of being very militaristic. Thus even those who did not want to follow Hitler would patriotically do their duty for the Fatherland.
Also, by late 1943, Italians had a choice of which side to fight for, forces being raised for both sides 
See also this previous discussion:
I laughed out loud, for real.
Backed out? Mussolini did all that shit his own self, not at Hitler’s orders.
As yellowjacketcoder worked out, I was referring to the end of WWI - the Treaty of Versailles pissed off a lot of people; the ‘stab in the back’ idea wasn’t invented by Hitler, he just exploited it. Without Dolfy the details would have changed, but a catastrophic war involving Germany was coming regardless.
Such “waste” can be deliberate: whichever side wastes more, loses. Putting Allied divisions to “work” in Italy was thought superior to leaving them in garrisons.
Anyway, without Axis operations in Italy and Africa, the Brits could have dominated the Mediterranean, kept Suez open, and opposed German intrusion into the Balkans and Greece. Turkey would have been more likely to join the Allies; a Soviet supply route alternative to the perilous Barents Sea might have been established. Whatever one thinks of Italian competence, its geographic position was important to Axis success.
Like I said, he was an idiot. But if he hadn’t been, and decided in 1940 that getting involved was not a good idea, could he have backed out?
Hitler was a jerk.
Mussolini bit his weenie, now it doesn’t work.
There were alternate supply routes. The Arctic convoys tend to get the most attention as they could be very dangerous, but it was actually the least used route accounting for ~23% of lend-lease aid to the USSR. The other routes were the Persian Corridor after Iran was occupied at ~27% and via the Pacific at ~50%. From wiki:
I find the claim that only non-military goods could be transported via the Pacific Route highly suspect; it’s the first I’ve ever heard of it and it isn’t what the cited source actually says. US freighters using the route were reflagged as Soviet after Pearl Harbor.
Probably. After all, Franco (who, BTW, is still dead) did go “Thanks for helping me deal with that popular and democratic movement I was having problems with, Mr. Hitler ! Helping you in return ? Haaaahahahaha. No.”
(yes, I know it wasn’t that clear cut, and that in practice Franquist Spain did materially support the Nazi regime. But never officially.)
While it would have been better for the entire war effort for all if the Italians had stayed out and the Med a quite area, once it started it was quite important especially to Germany. If the Mediterranean was lost, all of Southern Europe was exposed. Fortunately, Hitler put off supporting his forces there when success could have been spectacular, and sent a whole Army Group when defeat was assured.
It wasn’t just WWII, Italian fascism made a whole list of blunders that cost Italy dearly, and brought little or no wealth:
-Libya: mostly desert; the Italians colonized it (it cost more than it was worth). Vast stores of oil, but missed by Mussolini’s geologists.
-Ethiopia: conquered at vast cost, next to worthless
-Somaliland: ditto
War makes sense if you can steal wealth from counties you invade-none of these conquests"were worth the cost. And palling up with Hitler (invading Russia), cost the Italians hundreds of thousands of lives.
Palling with Hitler? Didn’t Il Duce screw things up for Hitler by attacking Greece and attracting the British to the Balkans, thus diverting German troops (Barbarossa) until they collided with the Russian winter!
Upon meeting with Franco and trying to convince him to enter the war, Hitler famously said he’d rather have his teeth pulled out than converse with Franco again; by all accounts Franco was the only person in the world who could out-talk and out-bore Adolf Hitler. He apparently basically yammered for three hours straight without really saying anything, and was (unlike anyone in Hitler’s circle) willing to point out uncomfortable gaps in German plans, like “I don’t think you can invade England successfully” and “you don’t seem to have a way of beating the Royal Navy.”
If Spain could stay out of the war surely Italy could have too. German benefitted from Spanish neutrality, and would have benefitted from Italian neutrality.
No, operations in the Balkans did not delay the launching of Barbarossa, the weather and lack of logistical preparations did. The tentative start date for Barbarossa was set for May 15 but was pushed back to June 22. Operations in Greece were completed on April 30, and German forces used in the Balkans were back in position for the launching of Barbarossa by mid-May. Spring 1941 had been particularly wet and the rivers in Eastern Europe were at flood into late spring. Even had the weather not been particularly bad, May 15 was probably too optimistic of a start date to begin with.
The idea that the operations in the Balkans delayed the launching of Barbarossa by six weeks and that those ‘lost’ six weeks saved the Soviet Union stems from the understandable desire to give some meaning to the British defeat in Greece. Not only had Britain been quickly kicked off of the continent again, the forces sent to Greece had been pulled from North Africa where the British had the Italians on the ropes pushing them back through Libya. Had the forces not been diverted to Greece, they might have driven the Italians out of Libya, ending the North African campaign in spring 1941. As it turned out, the arrival of the Africa Corps prevented Italian defeat and the fighting in North Africa would continue for two more years. Barbarossa also didn’t fail due to the Russian winter; it failed due to the Red Army, the vast distances in Russia and logistics.
Still, Mussolini’s poor excuse for “strategy” couldn’t have been much help to the Axis’ objectives.
Let me mention this: If the US army hadn’t fought in North Africa and Italy wouldn’t the US troops making the Normandy invasion have been completely inexperienced in combat? Well, except for the veterans of WWI. I doubt they’d have brought in experienced combat troops from the Pacific Theater of Operations.
How much experience did they have? Only one (the 1st aka “The Big Red One”) of the four infantry divisions that landed on the Normandy beaches had fought in North Africa and Italy. The 4th, 29th, and 90th had never fought in combat before Overlord. Same thing with the 2nd and 5th Ranger Battalions - Overlord was their first combat in WWII. The 82nd Airborne had fought in North Africa and Italy but Overlord was the first battle for the 101st Airborne.