The Islamic Republic of Iran
Whenever the United States of America backs the wrong side in the geopolitical sphere and it loses it holds a grudge. Such is the case in regards to the Islamic Republic of Iran (and the People's Republic of China and North Korea, Cuba, Venezuela but we'll get to those later).
In 1953, when Iran had a version of a "western styled democracy", with Mohammad Mosaddegh as the Prime Minister (it was called the Imperial State of Iran, in 1953) that wasn't good enough for the American and British governments - so the United States in collaboration with the British performed a coup that removed Mosaddegh from leadership and made Mohammad Reza Pahlavi supreme autocrat dictator (their useful idiot) - which lasted for 26 years - until in 1979 he was overthrown and a Islamic Republic was declared under the leadership of Supreme Leader Ayatollah Ruhollah Musavi Khomeini. The Current Supreme Leader, Seyyed Ali Hosseini Khamenei, has been Iran's Supreme Leader since June 4 1989 one day after the death of Ayatollah Khomeni who died on June 3 1989.
AS Prime Minister, Mohammad Mosaddegh had nationalized Iran's oil company for the sole benefit of its citizenry - that's what precipitated the coup. Sadly,when he had the chance Mosaddegh should have deposed Pahlavi, abolished the monarchy as had earlier been done in Egypt to King Farouk in 1952 - then sent him into exile or hanging the bastard.
Today the Iranian nation is hated for not just kicking out their puppet Mohammad Reza Pahlavi, but also for merely being Muslims - the deep seated hatred towards Iran in particular is by far the most hateful version of Islamophobia that exist.
The nation of Iran hasn't done one single act to the United States of America that it didn't have coming to it as the aggressor. The United States picked a fight with them - first - not the other way round. It's the United States of America that drew "first blood."
The Supreme Leader of the Islamic Republic of Iran - Grand Ayatollah Seyyed Ali Hosseini Khamenei 
President of the Islamic Republic of Iran, Ebrahim Raisi
In Regards to the JCPOA - Joint Comprehensive plan of Action of July 14 2015.
In short, the JCPOA was an agreement between the five permanent members of the United Nations plus one - Germany and the EU - to curtail enrichment of uranium by the state of Iran in exchange for sanctions being lifted against the nation. it was signed in 2016 and 2 years later when Donald Trump became president he took the United States out of the agreement rendering it null and void for all intents and purposes.
In reality Trump's withdrawal from the agreement actually did Iran a favor because when we observe the genocidal behavior committed against an imprisoned people in Gaza by the apartheid Israeli regime you can clearly see that the only protection the state of Iran would have against being one day attacked with nuclear weapons by the Israelis would be to have their own nuclear weapons arsenal - that they should now pursue nuclear weaponry with the enthusiasm of an evangelist.
To my mind the height of irresponsibility by the leadership of Iran would be NOT developing nuclear weapons (actually they should have acquired the technology from A. Q. Khan, the father of the Pakistani nuclear weapons program when he shopped it around) to protect their nation from these rabid zionists murderers. Without the equal ability to erase Apartheid Israel from the face of the earth with nuclear weapons as well (Mutually Assured Destruction) - there, the Islamic Republic of Iran stand in much peril.
My deep disdain for the murderous Apartheid Israeli state goes out the door and round the block. The reality is that shouldn't have even been allowed to come in existence in the first place - in 1948 - if all the rules set forth by previous agreements between nations were adhered to. They've been allowed to do what no other nation in history was allowed - to murder their way into existence (here).