If we define
strategic effect as having a change to policy/strategy as a result or consequence of action or other cause... I'd like to offer a few counters where
independent strategic effect has been airmailed in:
1.
Battle of Britain. The Luftwaffe inability to achieve air superiority and thus protection of the channel crossing led to cancellation of Operation Sea Lion - demonstrably a decisive change to German overall strategy.
2.
Battle of Germany. The defeat of Luftwaffe (as directed in Point Blank Directive, an outcome of Casablanca directive), in concert with the transportation plan were direct enablers of D-Day landings; key enablers to the allied strategy.
3.
Operation Allied Force. NATO Air Forces defeated Serbian forces, and undoubtedly drove the changing of Slobodan Milosovic's Strategy.
Plenty of
strategic effect... achieved through AirPower, not just airlift...
Key word in my statement was independent. Air power proponents like to sell that air power answers anything and can hence replace land/sea power; my argument is that is incorrect for anything that is not airlift. Taking your examples as evidence:
The Battle of Britain helped cancel German plans, but its wasn't the main reason. The existence of the Home Fleet provided that strategic impetus. Both German and British sources identified that the Royal Navy would sortie to stop an invasion fleet, regardless of the air situation. Remember that the Royal Navy had already bloodied the Kriegsmarine's nose during one invasion, and that wasn't in defence of the Home Islands. The success of the RAF helped reduce that likely cost to the Royal Navy, but between the fleet and Berlin's shift to the east, it did not do it alone.
In reverse, the defeat of the Luftwaffe was an enabler of D-Day, but again, in isolation it did not achieve anything. The defeat or otherwise of the Luftwaffe meant nothing without the commitment of sea and land power on 6 Jun 44 - and in many ways was irrelevant if you don't care how far west the Soviets come. Yes, the CBO helped pull guns off the Eastern Front and helped get the Soviets through 42/43, but it didn't achieve anything independently.
This is the closest I think you can get to, where kinetic airpower has achieved strategic effects. Except, one of the overlooked points was the increased efforts in putting a NATO ground force into action. It was fairly clear to Serbia they could not win against a ground invasion, especially without support from Moscow, but they could hold out long enough for the international pressure on the questionable actions of NATO (as in, legally questionable to start bombing, not Takao thinks intervening was questionable) to stop. KFOR rolls in within 2 days of NATO ratification of Serbia's surrender - a clear sign that it was poised and ready to go in for combat operations (which is true). Again, air power helped, but the increasing threat of ground forces forced Milošević 's hand.
In all of those situations, the air power contributed, but could not independently bring about the strategic effect. In at least two of them, the naval and/or land forces could have achieved the same result without air power (at more time and expense). Compare to the Berlin Airlift (and arguably Operation Nickle Grass) where neither land nor sea could achieve what air power could. Compare the post-war history of the RAAF, where the fighters and bombers didn't really achieve any strategic success, but our Caribou's, Herc's and C-17s along with transport helicopters have been at the forefront of many Australian diplomatic efforts in the region. I know there is a claim about F-111s influencing Jakarta, but I've never seen any evidence of that (despite asking here and elsewhere, including work, multiple times).
I'm all for an Air Force. Given the option of fighting under a sky owned by REDFOR or a sky owned by red kangaroos, I'll take the later every single day. If I am ever involved in ground combat operations again, I want there to be a 50 000ft high stack of kangaroo's armed with bombs, rockets, missiles and cannons - all designed to rain a bunch of HE down on REDFOR's head so my men and women can operate safely. What I do draw the line at is when people lose sight of the real limitations of airpower, and the fetishization of pointy, fast, grey things. The latter isn't air specific, but the air domain is where it is most prevalent. And, given Australia's current resource pressures and strategic situation, I think spending money on more fighters is one of the worst things we could do. And, if you have to force me into buying platforms, it'll be airlift before anything else.