The United States and most of Europe are united in their concerns about Iran's nuclear program. Fully 82% of Americans say Iran developing nuclear weapons would be a major threat. Large majorities share this sentiment in Spain (81%), Germany (79%), Italy (78%), France (74%) and Britain (68%). Across the 14 nations surveyed, the median percentage rating a nuclear Iran a major threat was 66%. However, in Russia, a nation that is crucial to any effort to impose international sanctions on Iran as a permanent member of the United Nations Security Council, just 41% say Iran's nuclear program poses a major threat. In fact, a plurality (48%) considers it a minor threat or not a threat at all.
Source: Pew Research Center