US will definitely suffer if it leads strike on Syria. Is that TRUE?

As the ramifications of a grisly chemical weapons attack loom over a summit of world leaders, some of Syria's staunchest friends blasted what they call the "arrogance" of U.S.-led efforts to strike the war-torn nation and said those who do will pay a steep price.
Iran's Ayatollah Ali Khamenei said Thursday the United States -- which, in addition to being one of his country's chief adversaries, has led the push to punish Syrian President Bashar al-Assad's government over chemical weapons -- has no right to make "humanitarian claims (given) their track record" in Iraq, Afghanistan and at the military prison in Guantanamo Bay, Cuba.The turmoil in the Middle East, Iran's leader said in remarks reported by state-run Press TV, is a "reaction of the global arrogance" that is rooted Washington. Should the United States and allies strike Syria, he added, it won't be able to "eliminate (the) resistance."
"We believe that the Americans are committing a folly and mistake in Syria and will, accordingly, take the blow and definitely suffer," said Khamenei.He spoke on the same day Hezbollah issued its first official statement since the effort began to strike al-Assad's forces in the wake of an August 21 chemical weapons attack outside Damascus that, the United States estimates, killed more than 1,400 people, many of them children.The group, which is popular in parts of the Arab world yet labeled a terrorist organization by the United States, claimed that any military action against Syria's government is "a form of direct and organized terrorism."
"These threats fail to conceal the true objectives of this strike aimed at mobilizing Israeli (strength) in the region in an attempt to impose the Western colonial grip," Hezbollah alleged in a statement read by parliamentarian Hassan Fadlallah, as reported by Lebanon's official National News Agency.
The remarks from Hezbollah and Iran are significant, given concerns that international military intervention in Syria could set off a wider war that further destabilizes the region and, thus, the world. Based in Lebanon, Hezbollah is linked to numerous terrorist attacks and is one of Israel's chief adversaries. So, too, is Iran, which has been at odds with Washington and others for years regarding its nuclear program.Still, U.S. and other leaders continue to press for military action against Syria's government -- taking their arguments, through Friday, to the G20 summit in St. Petersburg, Russia.
Before heading east, U.S. President Barack Obama said that he believes the world has a duty to act, saying a failure to do so would give those with chemical, biological and nuclear weapons carte blanche to use them on anyone.
Arguing that "the international community's credibility is on the line," the president said, "The moral thing to do is to not to stand by and do nothing."
Yet Russia, which repeatedly has used its veto power to block U.N. Security Council efforts targeting al-Assad, has pushed back. They accused Washington and others of being overzealous and bull-headed by ordering strikes without irrefutable proof Syrian leaders are responsible for using chemical weapons, something they don't publicly believe.