Iran has long been involved in the sponsoring and support of worldwide terror groups and has been officially implicated for its involvement in terrorist activities in several Western states. It provides aid in the form of weapons, training, and funding to Hamas and other Palestinian terrorist groups, Hizbullah in Lebanon, Iraq-based militants, and Taliban fighters in Afghanistan.
Iran's behavior over the past several years suggests that it is actively pursuing a nuclear weapons program. While denying these allegations, Iran's behavior has led to its being sanctioned by various international bodies, including the IAEA and the U.N Security Council.
In the past decade, Iran has pursued all stages of developing nuclear weapons, including mining uranium, converting uranium to uranium hexafluoride, enriching uranium hexafluoride to obtain high-grade fissile material necessary for military use, and developing an implosion system needed for the detonation of nuclear devices. All this despite Iran's commitment to and ratification of the Treaty on the Non-Proliferation of Nuclear Weapons. In addition, Iran has developed weapons systems - primarily medium- and long-range ballistic missiles capable of delivering nuclear payloads to countries in the Middle East, Europe and soon North America.
In addition, Iran continues to violate and disregard the human rights of its own citizens, and represses freedom of the press, freedom of association, freedom of religion, equality, and children's rights.
Iran publically denies the Holocaust, and is the only country that openly calls for the annihilation of another state - the State of Israel. Furthermore, Iran has been developing and testing rockets that it boasts can, and will, be used to wipe Israel off the face of the earth.
Prime Minister Benjamin Netanyahu (17 Feb 2010):
"We are threatened by an extremist form of Islam, headed by Tehran, which sends out its tentacles in the form of Hamas and Hizbullah and other terrorist organizations, which undermine the very existence of the State of Israel and speak openly about their desire to destroy it. This is not just a threat against Israel, but against the entire world...
There are tens of millions of people in Iran, the vast majority, aspiring to one thing - freedom from this brutal tyranny."
Prime Minister Benjamin Netanyahu's address to the UN General Assembly (1 Oct 2015):
"Last month, [Supreme Leader of Iran] Khamenei once again made his genocidal intentions clear before Iran’s top clerical body, the Assembly of Experts. He spoke about Israel, home to over six million Jews. He pledged, “There will be no Israel in 25 years.” Seventy years after the murder of six million Jews, Iran’s rulers promise to destroy my country, murder my people...
But don’t think that Iran is only a danger to Israel. Besides Iran’s aggression in the Middle East and its terror around the world, Iran is also building intercontinental ballistic missiles whose sole purpose is to carry nuclear warheads. Now remember this: Iran already has missiles that can reach Israel. So those intercontinental ballistic missiles that Iran is building – they’re not meant for us. They’re meant for you. For Europe. For America. For raining down mass destruction – anytime, anywhere."