Former US Secretary of State Condoleezza Rice on Wednesday hailed Mitt Romney as the leader who can rescue America from foreign and domestic threats that she said have flourished during Barack Obama's presidency.
The former top US diplomat said the Democratic president has abdicated responsibility in global crises where US leadership was needed - most recently in the Middle East.
"We have seen that the desire for liberty is universal as people in the Middle East rise up to seize it," said Rice.
"Yet the promise of the Arab Spring is engulfed in uncertainty and hostile neighbors."
Other foreign policy failures span the globe, she said "from Israel to Colombia, from Poland to the Philippines."
"Mitt Romney and Paul Ryan understand this reality," she continued.
"Our well being at home and leadership abroad are linked. They know what to do. They know that our friends and allies must again be able to trust us."
Rice delivered her address - the key foreign policy speech during the Republican Presidential Convention - as the lone hold-over from the Bush era to take part in the coronation of Romney as the Republican presidential candidate.
She made the case that Romney would be an able leader of the free world.
Rice was known as something of a hawk during her eight years - first as national security adviser, then as secretary of state - in the George W. Bush administration.
She played a key role shaping US policy toward Iraq and Afghanistan - two controversial and unpopular military engagements that continue to exact a heavy toll on the US purse and its overextended military.
Rice said that while Romney is interested in peace, under his administration, it would be "peace through strength."
"Our allies and friends have to know that we will be reliable and consistent and determined. Our foes can have no reason to doubt our resolve because peace really does come through strength," she said.
Mitt Romney and Paul Ryan understand this reality," the former top US diplomat continued.
"They know that our friends and allies must again be able to trust us, from Israel to Colombia, from Poland to the Philippines," she said.
Critics of the Bush era and Rice's role during the US-led military intervention in Iraq, feared her speaking role augured a return to war-mongering and accused Romney of having "outsourced" his security and defense policy.
"I am troubled by Republicans' choice to hand what little platform for national security they have over to Condoleezza Rice and John McCain," said retired Major General Paul Eaton from the National Security Network.
"While I respect Secretary Rice's talents, the Bush-Rumsfeld-Rice team perpetrated what I consider the most egregious US national security failure of the last half-century, namely, the disastrous decision to invade Iraq without the resources or exit strategy needed to execute a responsible military campaign.
"Romney's choice today to outsource discussion of foreign policy to neoconservative ambassadors to last decade's reckless security catastrophes is deeply concerning to the military community," Eaton said.