You have just picked the worst country as an example...View attachment 170931
Egypt, which is firmly under US and IL control could be utilized as a regional hub, from which the main Invasion force could be organized. The full scale deployment of the USAF and USN (meaning the entirety of the USNs CSGs and amphibious assault groups that could be surged) would precede the large scale Invasion staged by the US Army and Regional allies. I.e. suppressing Iranian forces with all means avilaible in order to move in troops from Egypt through Jordan and Iraq. Possibility of an amphibious Landing from the arabian sea is there, but I doubt that would yield results. And even a hypothetical, more risk taking US would still not take such a high risk relatively meager reward action. Supply lines and staging areas could be moved further towards to Iran (meaning into Iraq, Jordan, perhaps Syria) if the offensive capabilities of Iran are deemed sufficiently weakened. This doesn't mean that there would be no Iranian strikes, they'd just be degraded in intensity and have longer intervals between them.
This is what I meant that while possible on paper, and while the US has the most robust logistics of any military force, this might push them to the brink.
Egypt always refused the existence of a foreign base or troops in it's land expect after 1967 for soviets, north korean and others, so that they protect their mainland against Israel and it's US backing.
Nor does Egypt in any way accept US-Israel attack on Iran -- look at the government, media and the people.
The only way for them is basing in the gulf after some time, eapecially in KSA, Kuwait and UAE.