Retired Adm. Gary Roughead, who stepped down a year ago as the top Navy officer, expressed concerns about the consequences of a U.S. or Israeli attack on Iran’s nuclear facilities.
“I think a military strike into Iran would set off a whole set of events,” he said when asked about a possible Israeli or U.S. strike against Iran in the coming years.
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Iran has an estimated two-dozen nuclear-related facilities that would be targeted in a military strike. Many of the facilities are in underground bunkers that are difficult to target.
The nuclear facilities and the country at large also are protected by sophisticated anti-aircraft defenses that would make a military strike complicated.
Full article: Pressuring Persia (Washington Free Beacon)
Global Geopolitics 
It may be difficult to strike Iran now, but once they have a nuclear deterrent it becomes impossible. Maybe the US government knows something we don’t. Does Iran already have WMD? What’s ironic is that when the US and it’s allies attacked Iraq they claimed it was because they had WMD that could strike Britain in 40 minutes, but if they actually believed they had one they would never have risked an attack.