Tensions between the United States and Iran heightened after the Arab nation declared it wouldn't stop its nuclear program, and a U.S.-born Iranian man was sentenced to death by an Iranian court.

In the first development, the Iranian supreme leader, Ayatollah Ali Khamenei proclaimed his nation would not give up its nuclear program, despite the economic damage done by international sanctions.

"The strong decision of the sacred Islamic republic is based on not being diverted from the path it has adopted, not surrendering, and resisting against bullying and extreme demands of superpowers," he said through a translator.

The Iranian government insists that its nuclear activities are for peaceful energy purposes only, but this is disputed by the U.S. and its allies.

Secretary of Defense Leon Panetta repeated international demands that Iran stop enriching uranium.

"But we know that they're trying to develop a nuclear capability, and that's what concerns us. And our red line to Iran is, do not develop a nuclear weapon. That's a red line for us. They need to know that, if they take that step, that they're going to get stopped," said Panetta.

Tensions were also high because Iran sentenced to death a detained U.S.-born Iranian man charged with spying for the U.S. intelligence agency, the CIA.

According to reports, Amir Mirzaei Hekmati is a former U.S. Marine and military translator. Born in Arizona to a family of Iranian descent, he is said to hold dual citizenship. He was detained in Iran last August and tried for espionage last month.

In Washington, White House spokesman Jay Carney rejected the charges and the death sentence.

"They need to know that, if they take that step, that they're going to get stopped." - Secretary of Defense Leon Panetta.

1. Where is Iran?

2. In the video, the Iranian supreme leader, Ayatollah Ali Khamenei uses the term
"Islamic republic." What does it mean that Iran is an Islamic republic?

3. Which countries does the U.S. traditionally have good relations with? Which countries does the U.S. traditionally have bad relations with?

1. What is enriched uranium?

2. What has Iran said it is using the uranium for and what has the U.S. said in response?

3. In your opinion, why doesn't Iran want to give up its nuclear program? Discuss.

4. What other countries have nuclear weapons? Does the United States consider any of them threats?