There is some research into using high-altitude unmanned airships as surveillance platforms or communications relays. It’s touted as an inexpensive substitute for satellites. Google for “stratospheric airship” if you want to look for more info. Sanswire is one of the companies working on it, though they haven’t actually built a functional prototype.
For this zeppelin to work, I think they’d have to make it out of Led. Only a Led Zeppelin would rock hard enough to defeat the enemy.
Um, a hundred thousand feet is 18.9 miles, not one mile. You are already out of range of most of the world’s military arsenals. And you are only that close to things that are shooting straight up. And, given even halfway decent stealth capability, most of the very few systems that can reach you won’t be able to see you without illumination from ground stations. That’s probably more dangerous for the AA forces than for the LTA.
It could work like this. I have three of these high altitude sensor vehicles loitering over my theater, full time, day and night, for operationally permanent deployments. They send their signals upward, to satellite relays, which send down to ground units in theater. Someone uses radar that isn’t on my list, I add the gps coordinates of that sighting to an ongoing hot database. Some other asset, whether ground, or high speed air responds with a time delay variable to alert status, possibly within seconds during very high alerts.
The vulnerable observation vehicle is entirely passive emission wise, other than to the very narrow region where the relay satellite is. It is a poor radar target, or even nearly radar invisible. It is a very poor visual target at 19 miles above you, and you have very few assets able to reach it even if you do find it, and it can go away and hide, while its two brothers triangulate on you. The operators are at base camps, somewhere in the several hundred mile region, getting the live feed, and controlling the craft, and its sensors. They do shifts, and are always fresh, and rested.
If you are worth a significant strike, they can send live streaming video to an entire heavy division giving real time updates on your position, force composition, and movement. Meanwhile, their air arm is getting the same information, in case you have enough force to be worthy of a combined arms counter attack.
But, no one in their right minds engages in a symmetrical force on force attack on a world power. The kind of war you fight against the sort of enemy we are is the one you see working every day. You always attack your enemy at the weakest point, and our weakest points are political, social, and economic.
Tris
I would think that you would go the opposite way. Instead of a prox fuse and shrap , you would have a delayed fuse with a shaped charge.
Either the Zep skin is going to be metal or a kevlar composite, so your going to want to bury the warhead deep inside the zep and break the spine/keel when it goes off.
Another thing to keep in mind is that the size that OP posts is big enough to have a good ECM suite onboard and a bomb bay filled with HARMS.
Declan
Big Zeps are very liable to bad weather, as per the USS Akron and Macon. That’s why we don’t use them. Sorry. 
What would the drift factor for a heavyweight zeppelin with some form of heavyweight plating be? If they’re keeping an altitude of 90’000ft+, how much would it affect them?
What’s the maximum altitude that the SAMs possessed by, say, the Taliban, can reach?
You should market that idea, it could be your stairway to heaven.
Combat Zeppelin might be a good video game.
Actually, the only pure weather loss for a US zeppelin was the USS Shenandoah. She flew into a microburst storm and that did break her back. Both Akron and Macon were lost because the helmsman on duty flew them in a storm at such a steep angle that the storm winds broke their backs. Thus, Akron and Macon AIUI are both considered losses due to operator error.
I’ll admit, that doesn’t change your point that a zeppelin is vulnerable to weather in ways that an airplane isn’t. But at least part of the poor reputation that zeppelins have for airworthiness is exaggerated.
I’m inclined to believe that even if we could prove that our zeppelin (well, more likely semi-rigid blimp) were feasible, we’d have a very hard row to hoe to sell anyone on it. The way I read the capabilities for our zeppelin it’s observational capabilities seem to be a match for Global Hawk 's (In fact, to save us development costs, let’s just steal some Global Hawk surveillance suites.) so the only real improvement is in duration over the theater of operations. Which something like Global Hawk could provide through redundancy of platforms. And it already exists.
Oh, one more note for anyone thinking of armoring a blimp: If the navies of the world have decided that armored ships are a waste of resources in this missle prevalent era, there’s no way that you can armor an aircraft of any kind sufficiently to withstand a missile strike. You may prevent the loss due to current SAM or AAM warheads, but developing a new warhead would be pretty easy - simply start with any number of Anti-tank warheads drop the weight a bit, since there is going to be no way to take inches of armor airborne, presto-chango, you have the beginnings of your new APSAM.
And of course, by adding conventional armor, any chance to build a stealthy blimp goes out the window.
True. However, the OP spoke of “an altitude of a mile or more”.
The problems of maintaining a lighter-than-air craft on station at 100k’ are formidable. It would have to be huge to carry even a modest payload (since air density at that altitude is about 1.5% of that at 5000’). It would need powerful engines and large props to cope with occasionally strong winds. Engines would have to be electric (can’t be air-breathing at that altitude) so would need heavy batteries for energy storage.
It probably wouldn’t be necessary to go nearly as high as you propose to get most of the benefits. But the engineering challenges would be large at any high altitude.
No need for a satellite relay - from anything like 100k’ the direct link would work to a considerable distance - probably at least 200 miles.
I’m not so sure. To carry a Goodyear-blimp-sized payload (i.e. small) it would need to be something like 800’ long. Can you spot a 70-story building from 20 miles? How about a B-747 at cruise altitudes? (The 747 is 230’ long and cruises at around 35,000’ - so it subtends a smaller angle than would the airship.)
Have a tethered, armored, weather balloon in the center of a tempory base or secure point as a 100 meter platform for infrared cameras, long distance cameras, radar, and a remote GE mini chain gun.
The Ultimate in Home Security! 
The Kits could come self contained in a few crates with the canisters and deployable in a short time. Grunt friendly.
Just in case the OP is not aware, zeppelins were used as bombers during the first World War; they really broke a panic in London.
In theory, how fast could a lighter-than-air vehicle such as a zeppelin be designed to move?
Forgot the painter (Laser)…
Could put up one of those reflexive, active, lightcamo miniature blimps as an effectively invisible surveillance platform. That’s probably a weathership’s best use.
Normal cruising speed for the Graf Zeppelin and Hindenburg (late 1920s-1930s technology, airborne equivalents of an ocean liner) was about 100 MPH. I don’t have figures for the Navy rigids. My guess is that you could run a rigid built to modern technological standards on the order of 300 MPH – but that’s a WAG based on extrapolation, with no engineering behind it. Cruising range in excess of 10,000 miles.
For those of you thinking “big balloon” you’re thinking of blimps – same general shape but very different construction sand only a fraction the size of a rigid.
To picture one of these, imagine building the metal framework for a skyscraper of 40-50 stories out of aluminum (or a modern light alloy) in the shape of a cigar, then tip it on its side and fill 90% of the interior with large, tough gasbags. Give it a lightweight but tough exterior fabric skin to make it aerodynbamic and protect the interior from wind, birds, etc., and double tailfins in a cruciform arrangement (for horizontal and vertical steering), hang engines and a so-called “gondola” (actually something that looks like you removed wings and tail from an airliner, shaved off the rear top to match the curve of the fabric envelope, and consider the remaining 10% of the interior and the gondola as space for cargo, passengers, payload, and crew. You use no fuel to keep the thing in the air, just to move it (at neutral buoyancy) from place to place and to steer it – plus, of course, it can hover, by running engines at just enough speed to cancel present breeze. One of the suggestions when the whole rigid airship idea was brought back up 15 years or so ago was a heavy lifter, something that could act as a skycrane for multitun objects that need to be moved by air from specific locations to other specific locations.
I suspect the blimps they are making nowadays under black ops are delta shaped.