Biden set US up for a new war , by offering Israel Ironclad support no matter what and Bibi has been trying to get US into war with Iran for 20+ years.
If Israel strikes Iran , next round will not be per WWF/WWE rules and shit will get real fast in Israel, which will ultimately force US to intervene on Israel's behalf, which will also put US service men in bases in ME into a crosshair.
It is not possible for the United States to invade Iran given the realities of the limitations of American military capabilities.
The United States does not possess any force capable of conducting sizeable amphibious landings against contested well-defended beaches. The last time the Marines conducted a truly amphibious invasion that was contested was in Korea in 1950 and then Okinawa in 1945. The institutional knowledge is largely gone, the doctrine doesn't support such invasions, the training doesn't support such invasions, and the equipment doesn't exist in any appreciable numbers. The ability to land 1-2 Marine divisions on heavily defended enemy beaches? The USA doesn't have it.
The United States does not possess the ability to drop an entire airborne paratrooper division or land an entire air-mobile division to secure landings for amphibious follow-on forces or to secure airports to fly in additional forces.
Remember, the 2003 invasion of Iraq was conducted by staging significant forces in friendly and willing Kuwait, on the ground, with easy access by ground to Iraq. This amounted to almost 475,000 American personnel, 50,000 British, and several thousand Australians.
Today the entire British Army numbers about 76,000 personnel of all ranks, and their force is in disarray. Count the British out. They might send a token force of a few hundred or a few thousand, but don't expect anything more than a battalion or a regiment. Best to count them out.
Australia has its own problems worrying about China and the simple fact that the Australian Army has a strength of less than 29,000 personnel of all ranks. Possibly Australia sends a company, a battalion, or maybe a regime. Best to count them out.
The United States Marine Corps has 4 divisions, those being 3 active [1st Marine Division, 2nd Marine Division, 3rd Marine Division], and the 4th Marine Division. Total personnel as of 2022 are about 176,000 active and 33,000 reserve.
The United States Army has 453,000 personnel of all ranks [Active], 325,000 [National Guard], and 175,000 [Reserve]. This provides a total of about 935,000 personnel of all ranks in the US Army. I believe there are 12 Active Divisions and 8 National Guard Divisions, not addressing separate brigades or regiments of which there are several cavalry regiments, and airborne brigade combat team, and an armored cavalry regiment, among others.
Iran is a socially divided country with many young people, a lot of political polarization, and growing opposition to the regime. However, if foreign invaders show up, Iranians will likely unite behind their Ayathollah the way they did in 1980 when Iraq invaded. I would engage diplomatically and focus on the 18-30 year olds who will be ascending into power over the next generation as the current regime ages out. Military escalation with Iran will breed a new generation of hardliner zealots who want to realize "Death to America!"
Iran has at least 600,000 active duty personnel and 350,000 reservists, along with the Basij militia which theoretically provides 25,000,000 reservists although only about 500,000 to 600,000 are trained to a decent standard and available for immediate activation.
Thus Iran has 600,000 regulars, 350,000 regular reservists, and 600,000 paramilitary militia reservists available for immediate service.
Even assuming the United States could identify beaches and landing areas capable of accommodating largescale amphibious invasions, and assuming it had the ability to project 3 entire Marine divisions and 5-10 Army divisions across the world to those beaches, and supply them, this would strip bare all defensive commitments elsewhere in the world.
I believe it would take the entire ground component of the United States Armed Forces [Marines and Army] to even hope to have a reasonable chance of invading Iran, it is questionable if the initial invasion would succeed, and then even if the initial invasion proved a "success" (however defined), the forces would still have to fight from either the Kuwait/Iraq border region with Iran, or the southern shores of Iran, through numerous deserts and mountains, to Tehran and the other industrial population centers. Note, Kuwait does not actually border Iran, it is separated by a small part of Iraq, so the USA would have to stage forces in Kuwait and invade across Iraq to get to Iran via land, which would also start a war with Iraq and trigger attacks on a further extended and vulnerable supply line.
How would landing in southern Iran along the Gulf Coast work?
From Bushehr to Tehran it is about 700 miles through deserts and mountains. From Bandar Abbas to Tehran it is about 850 miles through deserts and mountains. This would also require the capturing of several significant urban areas along the way. This would also require holding open supply lines along the way. This would also be premised on Iran not closing the Strait of Hormuz which if it happened would totally shut down all of the Persian Gulf including ship based logistics support. Unless the US stockpiles 2 years worth of supplies in Dubai and keeps supply ships on the Dubai side of the Strait.
I do not believe the United States can afford an escalation with Iran because the United States cannot afford to escalate to actual war with Iran because the United States lacks the capabilities to defeat Iran in a conventional war.
If the United States launches air strikes against infrastructure in Iran and Iran responds by sinking American ships in the Persian Gulf and attacking American bases throughout the region, the USA cannot escalate to general conventional war because the USA has no viable way to prosecute such a war against Iran. This reality is dictated by the current global geo-political situation, US force strength, US force disposition, commitments in other theaters, domestic concerns, economic realities, and ultimately logistics.
The United States has no reasonable expectation or hope of being able to military overcome Iran in an initial invasion, capture and hold important population centers, keep supply lines open, and effectively occupy the majority of Iran. Some people may not like to hear it or want to hear it, but that is outside the capabilities of the United States.
The United States should rely on diplomacy to avoid any direct confrontation with Iran, especially if the confrontation would present a serious threat of escalation to general conventional war. The United States cannot win a conventional war with Iran. The only thing worse than starting a war is starting a war and then losing. If the price of avoiding war with Iran is cutting Israel loose, then we must cut Israel loose. The United States must come first.
When a politician says we should escalate with Iran and we should invade Iran, I often wonder, "Does this person understand geography? Does this person understand logistics? Does this person understand geo-politics? Does this person understand anything than money from the Israeli lobby?"