Regarding rbg81s points in comment #2, I cant really say that Ive noticed such stark differences among officers from different branches of services. Ive seen what I perceived to be studs and duds in all branches. Perhaps my perspective is due to being at lower echelons.
The one exception would be the comparison of the Air Force folks to civilians. I do think there is a big similarity, but I think it is intentional. Quite frankly, Ive always viewed that with envy for the same reasons that I would prefer Brown & Root to run the Army supply system. Civilians have always seemed more efficient and effective to me in technical areas, and the Air Force due to its overwhelming dominance in the air and other factors seems the most logical to tilt its focus more towards technical endeavors.
My father-in-law was a command pilot in B-24's and B-17's of the 8th Air Force. He has never said it, but the 8th Air Force was the most dangerous place on all the battlefields of the Second World War, including places like Sicily, Omaha Beach, and the Hurtgen Forest where my Regiment shed its blood. I don't think that he has much in common with the USAF of today.
The same can be said of all branches, in my opinion. Nothing is more awkward than a WWII veteran who scaled the cliffs of Point-du-hoc telling me and my peers that Im something wonderful. 2,500 dead American Soldiers in Iraq is a terrible thing, but that was just another day for WWII vets. We do one-year deployments in the Army. The Marines do 9-months (I think) and the Air Force does 4 to 6 months (I think). The WWII vets did multiple years and had a much higher chance of being killed, seriously wounded, and they were not eating at a catered chow hall, passing the day at Burger King, or getting massages. Most Soldiers in Iraq are living a life of luxury compared to their predecessors from WWII/Korea and earlier.
A destroyer wages war in three dimensions, on the surface against other ships and shore installations, under the surface in anti-submarine warfare, and in the air, anti-aircraft.
The captain must be highly trained in three dimensional warfare, plus the normal operation of a ship, plus the command of all men aboard.
The Air Force is one dimensional, same with the Army, except for anti-aircraft units.
It is apples and oranges to compare the command of, say an Army company, and an equal number of men on a destroyer.
I have to disagree with the assertion that ground forces somehow have a less complex mission. Were not fighting a two-dimensional war on a pool table. For the short time that I was a Company Commander, I had to contend with threats that were subterreanean (sewer systems, clandestine tunnels, etc), threats from the ground (IEDs, VBIEDs, small arms, RPGs, etc, etc), and threats from the air (mortars, rockets, even small arms) against both our ground forces and aircraft (organic UAV's and support attack aviation), as we policed a population of 125,000 civilians which doubled as the perfect camouflage for countless insurgents, dealt with media roaming the battlefield unsupervised (often simply disguised insurgent sympathizers), coordinated joint operations with Iraqi Army units that were heavily infiltrated with insurgents, Ministry of Defense Commando units, and Iraqi Police (heavily infiltrated with insurgents and also among the most poorly trained and poorly selected personnel in the area). Then I had to coordinate these with artillery, mortars, attack aviation, psychological operations, civil affairs operations, tactical HUMINT teams, intepreters, attached ODA's, attached forward air controllers, etc, etc, etc and make all of this fit in with our steady-state security operations, and ongoing attempts to understand and exploit tribal politics, ambitions of religious leaders, and about a thousand other complex factors. I only had about 100 Soldiers to do that with, while maintaining 30 vehicles, securing a patrol base, and doing the menial tasks that go into basic life support of the patrol base. Thats the short version. And that is what just about every other commander of every other Infantry Company was doing, most of us with 6 to 8 years experience under our belts, as opposed to 20. My Brigade commander (an O-6, and thus a better comparison to a Navy Captain) had 10 battalions to control over an area the size of a small state with at least 1 million civilians and a bazillion other factors. Please.
In the bigger picture, I would point out that the Army, Navy, and Marines each have lots of boats, aircraft, and ground forces. No one service is more multi-dimensional than another.
Thanks for your comments. My Dad was a tanker trained under Patton, a lifer who fought in WW2 and Korea. As such, I have high appreciation for the Army. However, to my Dad's chagrin, I went in the Navy. He and I have our good natured ribbing. Unlike you, he agrees with my three dimension distinction.