Republican Senator Chuck Grassley is joining a chorus of other Republicans who’ve been attacking President Obama’s foreign policy in the hours leading up to Obama’s speech at the United Nations.

“Now the world has come to expect something out of the United States and that’s our leadership,” Grassley said this morning during a conference call with Iowa reporters. “The strong, constructive leadership the world has relied upon from the United States seems to be very much at risk and the number one responsibility of the federal government in our constitution — that’s national defense (and) national security — seems to be at stake.”

Republican presidential nominee Mitt Romney has accused Obama of characterizing the murder of the U.S. ambassador to Libya as a mere “bump in the road” during a recent interview. An Obama aide has called Romney’s assertion “desperation and offensive.”

Grassley suggested this morning that Obama would have been better off meeting with foreign leaders who’re in New York City for the U.N. General Assembly rather than taping appearances on “The View” and other TV programs.

“Americans will decide in a matter of weeks whether they want his policies to continue,” Grassley said. “In the meantime and regardless of the outcome of the elections, no one can afford the lack of clarity that we’ve had from the president and the leadership the last two weeks to continue.”

Grassley is especially critical of the Obama Administration’s assertion that an anti-Muslim video produced in the United States is spawning protests in other countries.

“It’s baffling how the White House has blamed a video, an offensive video — obviously, for the violence and danger that’s erupted while refusing to realize the terrorist threat against Americans and the American way of life remains and is deadly,” Grassley said this morning.

About an hour after Grassley’s remarks, Obama condemned the video during his remarks at the United Nations and the president vowed the U.S. “will do what we must” to prevent Iran from getting a nuclear weapon. Romney on Monday said Obama’s foreign policy had put the U.S. “at the mercy of events rather than shaping the events in the Middle East.”

According to Grassley, there’s “no way” voters will “back up a president” who failed to react to warnings the life of the U.S. ambassador in Libya was in danger.