Voters fill in their ballots as they vote in the U.S. midterm elections at a polling place in Westminster, Colorado, Nov. 4, 2014.
Voters fill in their ballots as they vote in the U.S. midterm elections at a polling place in Westminster, Colorado, Nov. 4, 2014.

WASHINGTON - Three Republicans and one Democrat have officially declared their candidacies for the 2016 U.S. presidential election.  Already, foreign policy is a major issue in the presidential race as the United States is involved in efforts to resolve diplomatic and military conflicts around the world.

Democratic presidential candidate Hillary Rodham C
Democratic presidential candidate Hillary Rodham Clinton, center, speaks during a small business roundtable, April 15, 2015, in Norwalk, Iowa.

Former secretary of state Hillary Clinton is the lone Democrat and a major author of current U.S. foreign policy who is not expected to face a serious party challenge.  But there are several Republicans who also may join the race with first term senators Rand Paul from Kentucky, Marco Rubio of Florida and Ted Cruz of Texas.

Nearly 20 Republican presidential prospects discussed foreign policy at a conference that ended Saturday in New Hampshire, the small northeastern state that plays a large role in the presidential nominating process by holding the country's first primary election.  

Paul told the conference the United States often creates greater instability when it gets involved in chaotic places.  

He said some Republicans criticize President Barack Obama and Clinton for their foreign policy, "but they would just have done the same thing, just 10 times over.'' "There's a group of folks in our party who would have troops in six countries right now, maybe more,'' Paul said.

Paul didn't totally reject military force, saying he recently introduced a declaration of war against the Islamic State group.

Cruz was more aggressive.  He said, "The way to defeat ISIS is a simple and clear military objective.  We will destroy them.''  He said, "Twenty months from now, imagine a commander-in-chief who stands up and says with utter clarity, we will destroy radical Islamic terrorism.”

After announcing his 2016 presidential bid, Senato
After announcing his 2016 presidential bid, Senator Marco Rubio of Florida high fives son Dominic as wife Jeanette and son Anthony watch in Miami, April 13, 2015.

During an interview with CBS New's Face the Nation, Rubio criticized Clinton's policies for her "reset" with Russia, and her response to the deaths of four Americans in 2012 at the U.S. consulate in Benghazi, Libya.

"Today, our allies trust us less. Our enemies fear us less," Rubio said. "And America has less influence in the world today than it did four to six years ago."
Republicans regularly criticize President Obama's policies, but some would-be contenders have not made their positions clear.
Earlier in the conference, former Florida governor Jeb Bush, whose brother President George W. Bush authorized the 2003 invasion of Iraq, acknowledged a shift in his party against new military action abroad.  

He said, "Our enemies need to fear us, a little bit, just enough for them to deter the actions that create insecurity.''  Bush said restoring alliances "that will create less likelihood of America's boots on the ground has to be the priority, the first priority of the next president.''
South Carolina Senator Lindsey Graham said to defeat the militants, "You go over there and you fight them so they don't come here.''  He added if the militants are not defeated, the United States inevitably will have to send ground troops back to the Middle East to prevent another September 11-style attack.

Businesswoman Carly Fiorina called for a more decisive U.S. foreign policy. "The world is a more dangerous and more tragic place when America is not leading. And America has not led for quite some time," she said.
A U.S.-led coalition of Western and Arab countries is conducting airstrikes against IS targets in Iraq and Syria.  There also are American military advisers in Iraq helping Iraqi security forces plan operations against Islamic State in northern and western Iraq.

Clinton will be in New Hampshire this week.  She won the 2008 New Hampshire primary before eventually losing the Democratic nomination to Barack Obama.