Airships were routinely used and shot at in WWI, but very few were lost due to being hit.
If you think about it, it makes sense: they are massive, so the loss of pressure from a bullet hole isn't a real concern. And while the right hydrogen-oxygen mix is explosive, hydrogen needs oxygen to even burn. But there isn't any oxygen in the tank bladder. The escaping hydrogen can burn as it mixes with air if it finds an ignition source, but as long as your hull is from fire resistant material the flame can't do much, and is probably extinguished by the next wind gust.
Of course the "make your hull from fire resistant material" is where the Hindenburg went wrong. Her hull material could have been used at rocket fuel, the engineers just didn't realize that.
A quick scan of the Zeppelin list on wikipedia shows that significant proportion were lost after being hit by enemy fire. For example: LZ 20, 21, 22, 23, 28, 29, 32, 33, 34...
If you think about it, it makes sense: they are massive, so the loss of pressure from a bullet hole isn't a real concern. And while the right hydrogen-oxygen mix is explosive, hydrogen needs oxygen to even burn. But there isn't any oxygen in the tank bladder. The escaping hydrogen can burn as it mixes with air if it finds an ignition source, but as long as your hull is from fire resistant material the flame can't do much, and is probably extinguished by the next wind gust.
Of course the "make your hull from fire resistant material" is where the Hindenburg went wrong. Her hull material could have been used at rocket fuel, the engineers just didn't realize that.