There Is One Crucial Reason We're Talking About Boots on the Ground -- NYT opinion essay

[ancianita]

6. Considerations: Unlike North Korea, which is relatively isolated, Iran actively arms and funds proxy groups

across the Middle East (Syria, Lebanon, Iraq, Yemen), increasing the risk of nuclear technology or material proliferation.

Strategic Location/Oil Markets: Iran sits on critical global energy transit routes, such as the Strait of Hormuz, where a nuclear crisis could trigger global economic disruption.

Short Breakout Time: Although not yet having a nuclear weapon, Iran has accumulated uranium enriched up to 60%, just below the 90% weapons-grade, allowing for a fast, "breakout" to a bomb.

Nuclear Ambiguity: Iran's nuclear program is, "well distributed and hardened against attack," making it harder to destroy compared to North Korea's.

While North Korea has conducted six nuclear tests and can threaten the US mainland, it is already a, "nuclear weapon state". The Institute For Science And International Security notes that Iran is seen as a more immediate, unpredictable, and shifting threat.
Conversely, North Korea's threat is more mature and direct, with established, "delivery capabilities," but Iran's potential to trigger, "a regional war that could bring in the United States," often places it higher on the global threat list.

It's also worth noting that the secular history of the Shia nations, which are only 15% of the Muslim world, are the source of most armed conflicts. Their beliefs about "jihad" are externalized. Also worth noting is that primarily Sunni nations of the Muslim world that want to do business with the West.