Iranian Foreign Minister Mohammad Javad Zarif said one option "would involve resuming at a much greater speed our nuclear activities."
The U.S. gained an ally in Baghdad after overthrowing Saddam Hussein in 2003, but an alliance of Iran, Iraq, Russia and Syria is growing stronger.
Unexploded bombs from World War II are a persistent hazard in Germany, even more than 70 years since the end of the war.
With ISIS, Syria's universal enemy, largely defeated last year, international powers have begun to turn on each other in 2018.
Despite peace talks on the Korean Peninsula, Russia says the U.S. is risking a war with military exercises and "maximum pressure" against Kim Jong Un.
The RS-28 Sarmat could be seen taking flight as both the Russian and U.S. leaders discussed an "arms race."
The U.S. and Russia have both contributed to the fight against ISIS, but their goals for postwar Syria differ.
Vladimir Putin said the RS-28 Sarmat has no range limits and "is untroubled by even the most advanced missile defense systems."
North Korean supreme leader Kim Jong Un plans to pit the U.S. and China against one another in a game he thinks only he can win.
Iraq and Syria declared victory over ISIS in late 2017, but the U.S. and Turkey have resisted calls to withdraw their forces.
The tests come as Russian President Vladimir Putin revealed new nuclear missiles and Moscow's relationship with the West took another major blow.
President Donald Trump and North Korean supreme leader Kim Jong Un's meeting could signal a diplomatic victory, if nuclear war doesn't break out first.
Russia has chosen the names of three advanced weapons recently revealed by Putin, but what do they mean?
The U.S. military would need to evacuate more than 200,000 U.S. citizens and others in the event of a war breaking out with North Korea.
Having reached out for potential investment with South Korea, Saudi Arabia is talking tough against Iran's "Hitler."
Despite top U.S. defense officials urging Trump to stay in the Iran deal, Secretary of State Rex Tillerson was fired over his support for the agreement.
Secret war games attended by top U.S. military brass reportedly showed up to 10,000 American troops would be injured within days of the conflict.
Insurgents for the group overran three checkpoints in night raids on Tuesday.
But the total number of civilian casualties actually decreased in 2017, the U.N. said.