Iraq surrendered in 3 weeks and showed little to no resistance. The country had collapsed already both economically and psychologically. Most of the war was steamrolling for the coalition forces.
The US intended to test out and make a point about the supposed supremacy of its air power reliant doctrine. Add to it their low tolerance for casualties. As a result, it's probable that many more bombs were dropped than theoretically necessary.
This is a theory that hopefully will never be put to test, but sanity says that we should be well-prepared for all scenarios. You can't just assume things when it comes to national security.
In that case you can always doubt how secure you really are. Factual experience is the best indicator in this regard. The facts are:
1) Iran has been the biggest prize for the enemy since 9-11.
2) The enemy hasn't resorted to the military option.
3) Iran's position towards the enemy has been getting stronger with time.
So I'd argue Iranian decision makers and planners can be trusted. What they have achieved against all odds is unique, especially considering the complexities involved.
Yes, but it's worth it. And we can reduce our military involvement in Syria already. The war has reached a stalemate and Assad is not going anywhere, and neither is he going to kick Turkey out and unify Syria again.
I'm sure Iran will not be spending more than necessary on its military presence in Syria. And some form of Iranian boots on the ground will act as another deterrent versus the zionists and by extension the Americans.
Many factors must be taken into account when increasing the defense budget in such a manner, foremost political ones. Ten additional billions spent on the air force means slashing ten billions elsewhere. This too could negatively affect the stability and security of the country, albeit in an indirect way.
You can hit their airports but in a prolonged war, airports will be repaired and will become operational again after days or weeks.
If sirens ring every hour due to an incoming BM, their operation will be heavily compromised. Control, logistic, support and maintenance facilities at air bases can also be targeted, these are more time consuming and complicated to replace.