The president, as expected, nominated former Sen. Chuck Hagel as his next defense secretary on Monday.

Hagel is a decorated Vietnam veteran who served two terms in the Senate as a Nebraska Republican.

Still, the 66-year-old is already facing stiff opposition from some former GOP colleagues for his views on Israel and Iran. Several Republican senators say a stormy confirmation process is inevitable.

"If Hagel is nominated, it is very difficult to imagine the circumstance in which I could support his confirmation," Sen. Ted Cruz, R-Texas, said.

"It's interesting. The president seems bound and determined to proceed down this path despite the fact that Hagel's record is very, very troubling on the nation of Israel," Cruz continued. "He has not been a friend to Israel. And in my view, the United States should stand unshakably with the nation of Israel."

"And he has consistently advocated weakness with respect to our enemies, with respect to the nation of Iran. He has opposed sanctions over and over again," Cruz charged.

Ben Rhodes, Obama's deputy national security adviser, dismissed that argument.

"The president has a record of unprecedented security cooperation with Israel and that's going to continue no matter who the defense secretary is," Rhodes said.

The president is also expected to nominate counterterrorism adviser John Brennan to head the CIA.