White House hopeful Mitt Romney on Monday delivered a scathing attack on America's failure to lead the world at a time of upheaval, in particular in the Middle East, under the stewardship of President Barack Obama.

The Republican presidential nominee was seen trying to draw a sharp contrast with the incumbent just as there are only 29 days left before the November 6 election.

In a speech at the Virginia Military Institute, the former governor of Massachusetts asserted that the attacks on US consulate in Benghazi of Libya and American embassies in other parts of the world last month are no "random acts," but rather " expressions of a larger struggle that is playing out across the broader Middle East" now in the midst of the "most profound upheaval" in a century.

The attack in Benghazi on September 11 left US Ambassador to Libya Christopher Stevens and three of his staff dead, a tragedy that shocked America and the world.

Romney alleged that Obama has failed to use America's greatest power to "shape history" in the region, but instead chosen to lead from behind and leave "our destiny at the mercy of events."

As a result of the administration's inaction, Iran today "has never been closer to a nuclear weapons capability," and the conflict in Syria is threatening stability in the region, Romney claimed.

"It's clear that the risk of conflict in the region is higher now than when the president took office," he said.

Disputing Obama's claim as a crown achievement the killing of Osama bin Laden during his presidency, Romney said the achievement was won at a high cost while al-Qaeda remains "a strong force" in Yemen, Somalia, Libya and other parts of North Africa, Iraq as well as Syria.

"And other extremists have gained ground across the region," he added.

"Hope is not a strategy," he stated. "We can't support our friends and defeat our enemies in the Middle East when our words are not backed up by deeds; when our defense spending is being arbitrarily and deeply cut; when we have no trade agenda to speak of; and the perception of our strategy is not one of partnership, but of passivity."

Calling for a changed course in the Mideast, Romney said " America must have confidence in our cause, clarity in our purpose, and resolve in our might."

He said as president, he will not hesitate to impose new sanctions on Iran to force it to rein in its nuclear program and maintain aircraft carrier task forces in both the eastern Mediterranean and the Gulf.

"I'll deepen our critical cooperation with our partners in the Gulf, and I'll roll back President Obama's deep and arbitrary cuts to our national defense that would devastate our military," he said.

"I'll restore our Navy to the size needed to fulfill our missions by building 15 ships per year, including three submarines, " he added. "I'll implement effective missile defenses to protect against threats."

On Syria, the Republican said he will work with US partners to ensure the opposition has the arms needed to defeat the tanks, helicopters and fighter jets of the government forces.

The Obama administration is only providing non-lethal aid to the opposition for now.

Growth and jobs, not foreign policy, dominate the 2012 US presidential election. However, Romney is seen eager to show his readiness, to undecided voters in particular in the final stage, to lead on national security as commander-in-chief.

He will challenge Obama face-to-face on foreign policy, a strong point for the president, in the third and final presidential debate slated for October 22 in Boca Raton, Florida.