Or maybe they need nukes to do what they say they want to do, wipe Israel off the map. I think you should take them at their word. They're not a peaceful country. Israel has never attacked Iran and they have no disputed territory. Nonetheless, Iran repeatly threatens to destroy Israel and already uses proxy groups in the Palestinian territories and Hizbollah to attack Israelis.
ISIS claims responsibility for bombing in Baghdad suburb; death toll hits 21 (Reuters)
from the article: ANALYSIS: Iran likely to push the boundaries of nuclear issue