Hundreds of civilians, mostly in Iran, have been killed by dueling airstrikes despite international pleas for de-escalation.

President Donald Trump said the United will come down on Iran “at levels never seen before” if the Middle Eastern country attacks.

Iran's threats to the US are loud but not yet actionable, driven by anger over perceived American support for Israel's devastating strikes. The US's stern warnings and military buildup signal readiness, yet both sides seem cautious of direct conflict.

Former Vice President Mike Pence said on “State of the Union” Sunday that if Israel’s attack doesn’t somehow convince Iran to make major concessions in Trump’s diplomatic attempt to end its nuclear program, then the United States should be prepared to join the conflict.

President Donald Trump warned that "it's possible" that the United States "could get involved" in the ongoing Israel-Iran conflict if it continues to escalate during an exclusive interview with ABC News' Rachel Scott on Sunday (June 15).

While the U.S. insists it is not involved in strikes on Iran, American officials have confirmed military forces have been helping to intercept Iranian missiles fired at Israel.

The group is one of the most powerful and shadowy arms of Iran’s military, and it has long been on the front line of a shadow conflict with Israel.

Spokane-born retired American diplomat Ryan Crocker anticipates the conflict between Israel and Iran will escalate in the coming days.