Not sure what all the tit-for-tat is about Russia helping Iran. I can't work out if you are arguing or agreeing.
Iran supplies/supplied Russia with lots of drones in their war against Russia. Iran is one of Russia's top allies along with Belarus, China, India, and North Korea. Of course they are going to help Iran kill Americans. Based on history ... Putin will probably tell Trump that it's not true and based on Ukraine talks and the 2016 election, Trump will believe him over his own US intelligence community.
What I think are some of the bigger issues -
1. The war is illegal based on international law. Maybe that's not a big deal to some but I think it matters. From the web - Winston Churchill, along with U.S. President Franklin D. Roosevelt, initiated the foundational principles of the United Nations through the Atlantic Charter in August 1941, four years before the war ended. This joint declaration outlined a postwar world of international cooperation and self-determination, serving as the blueprint for the formal UN Charter signed in June 1945 --- this has been the basis of peace for 80 years. What trump (and Israel) are doing undermines this and makes the world less safe. Like the actions taken against Venezuela - it empowers Russia with former territories USSR. It empowers China with Taiwan. It breeds future hatred of the West by Iran.
2. This is a war of choice. There is no compelling reason to go to war with Iran. There is no imminent threat.Iran being bad actors is not a justifiable reason to go to war. After Venezuela I looked up how many dictatorships there are in the world. It's nearly 100. You want to go regime change all of them? Madness.
3. We did this with Iraq - it was a disaster that made the world LESS safe than it was before we went in. Thinking democracy and a stable country and government will spawn from reigning death and destruction from the skies is lunacy. Apparently the European leaders are more acutely aware of recent history and what a disaster Iraq was than the US. "you break it you own it" ... what follows is all on the USA and Israel. Anyone thinking this is going to have a positive ending is deluding themselves. Iraq, Libya, Afghanistan - all examples of the USA trying to police the world and failing miserably. And all of those examples were carried out by administrations that were more thoughtful and strategic than the idiot currently in the WH.
4. Iran - a country of 90 million - is unlikely to capitulate. Who knows how long or how many deaths will result from this war of choice. US personnel, allies, Iranians. . . I see the usual fake Christian cheering this action on. 75 thousand deaths of mostly innocent women and children in Gaza wasn't enough to satisfy their blood lust.. so on to Iran.
5. How many refugees and asylum seekers is the USA willing to take after we've bombed cities and displaced mass parts of the population? None. But it will create another humanitarian crisis in the middle east and across Europe. Just wait for the numbers of assylum seekers to sky rocket as they flee a country being ravaged by war. And then listen to all the right win politicians talk about how countries should keep them out. Hell we already have Trump and Vance criticising EU countries for their immigration policies. Just a little ironic how the USA is going to create 100,000's more for the region to deal with.
I'll ask again - what does success look like? In a month from now. A year? 5 years? .... what other countries do you want to add to the list where you support Americans implementing regime change?