US wants to rule the world and views China, Russia and Iran as a challenge to global hegemony.
Currently, Russia is bogged down in Ukraine, while China is incapable of invading Taiwan and US has to solve Iran's nuclear issue militarily BEFORE China becomes too powerful and Russia rebuilds its military.
Trump says this war with Iran will last for 5 weeks. US and Israel have 580 fighters in the region, but only 377 of them can conduct sorties against Iran with the rest being in maintenance cycles.
Lets assume 377 US and Israeli fighters conduct 0,4 sorties per day for 15 days (due to US bases being under attacks from Iran and due to Iran's air defenses) and after US suppresses Iran's air defenses these 377 fighters will conduct 0,7 sorties per day for 20 days.
So in total US and Israel can conduct 7.540 sorties against Iran in 35 days and with 1,5 targets destroyed per sortie US and Israel can destroy 11.310 targets in Iran with 22.620 JDAM munitions (10% of total JDAM stockpile).
Iran has around 4.000 ballistic missiles + 1.000 cruise missiles + 15.000 drones. With 50 ballistic missile launches per day and with 10 cruise missile launches per day and with 215 drone launches per day, Iran can destroy 3.100 targets over 35 days.
And still Iran will be left with 2.300 ballistic missiles, 650 cruise missiles and 7.500 drones.
So its US and Israel destroying 11.300 targets over 35 days and Iran destroying 3.100 targets over 35 days.
And if there is a full-scale war, US can bring in 2500 fighters of which 1600 fighters are combat ready with the rest being in maintenance cycles.
US has around 250.000 JDAMs and SDBs but US has to keep at least 100.000 of this as reserves for the European and Asian theatres. So US can use 150.000 PGMs against Iran destroying 75.000 buildings and structures in Iran with 50.000 sorties conducted by US military with 1600 fighters over 45 days.
In a full scale war US can destroy 75.000 targets in Iran before running out of stockpiles of PGMs, while Iran can destroy 6.500 targets across the region.
So in a limited 35 days war both sided will exchange strikes with US and Israel striking more than Iran.
In a full-scale war Iran will lay in ruins with 75.000 targets destroyed and Gulf oil infastructure destroyed and Strait of Hormuz closed with consequences for US economy being additional 5trln$ added to the Federal debt in 4 years and US economy being thrown behind by 5 years due to oil shock.