As Russia flexes its muscles in the Middle East by bombing rebels opposed to Syrian President Bashar al-Assad, here is a list of of every Republican candidate's views on the issue.

Donald Trump:

"If Russia wants to go in and if Russia want to fight -- in particular ISIS, and they do and one of the reasons they do is because they don't want ISIS coming into their country and that's going to be the next step. So that's why they're there," Trump said. "I think they will be fighting ISIS."

He called Syrian President Bashar al-Assad a "bad guy" who has killed hundreds of thousands of people, and that Russia is "probably trying to prop up Assad and help him out."

"We always give weapons, we give billions of dollars in weapons and then they turn them against us. We have no control. So we don't know the other people that we're supposed to be backing," Trump said of U.S. involvement in the region. "We don't even know who we are backing."

Dr. Ben Carson:

Vladimir Putin’s Russia has become dangerously belligerent. It is actively destabilizing Ukraine, endangering Europe in the process and continuing to fuel destabilization in the Middle East. This newfound aggressiveness is a rising threat to the peace and security of the American people.

The United States must be resolute in the face of these Russian transgressions. We must lead our allies, both NATO and non-NATO alike, from a position of strength.

History has painfully taught us that letting dictators run amok and hoping for the best fails.

President Putin must come to learn that there will be grave and serious consequences when Russia engages in naked aggression against other sovereign nations and free peoples. All options should remain on the table when dealing with international bullies such as President Putin.

Carly Fiorina:

Well, first, we know what’s going on. Syria and Russia, who have had a longstanding relationship, Iran, and Iraq, are forming an unholy alliance. Russia’s intentions are to shore up, and stabilize the Assad regime. ISIS is sort of a camouflage. There is no doubt, that Russia will be conducting airstrikes against anti-Assad rebels, whether or not they happen to strike a few ISIS folks as well is, I don’t know, to be determined. Here’s what we need to do immediately, I believe. First, not only can we not withdraw our air support, but I believe we must tell the Russians that we will conduct — we will secure a no-fly zone around anti-Assad rebel forces that we’re supporting. This is a tricky maneuver, it’s a dangerous maneuver, but it’s a maneuver that we must undertake, because we must make it crystal clear to Russia that they do not get to move into the Middle East, and become the dominant outside power, which is clearly their intention.

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You know, if you permit bad behavior, you get more bad behavior. So, hen we did not push back in any way on Russia’s aggression into Ukraine, we get more bad behavior. What I would do, as president of the United States, is immediately call together the Turks. I would start arming the Kurds. My goodness, the Kurds have been asking us to arm them for three years, we haven’t done it. We need now to engage the Turks, who have been asking us to work with them to secure a no-fly zone between the Turkish and Syrian border. We haven’t really done that, we need to. We need to arm the Kurds, and we need to pull together our Sunni Arab allies, who view all of these developments with great alarm, and provide them with the leadership, the support, the materiel that they need, to not only defeat ISIS, but also to stand up against Iranian, Syrian, and Russian aggression.

Sen. Marco Rubio (Fl.):

Over the last five years, I have consistently spoken out on the need to contain Russian aggression, even when it wasn’t popular. I have highlighted the dangers of the Obama/Clinton “reset” with Russia. And in 2014, I urged a rapid and forceful response to Putin’s annexation of Crimea.

As soon as I take office, I will move quickly to increase pressure on Moscow. I will impose a new round of sanctions on The Kremlin’s senior leadership and other Russian entities, including Gazprom, and will work with Europe to exclude Russia from the SWIFT interbank payment system.

I will immediately provide Ukraine with lethal military assistance and increased intelligence sharing to ensure that Putin’s violation of Ukraine’s sovereignty comes at a price.

I will impose visa bans and asset freezes against high-level Russian officials, and move to isolate Russia diplomatically by ceasing efforts to engage Moscow on issues not essential to resolving the crisis in Ukraine.

Under my administration, there will be no pleading for meetings with Vladimir Putin. He will be treated as the gangster and thug that he is. And yes, I stand by that phrasing.

The significance of Russia’s recent military activity in Syria cannot be downplayed. It is no less noteworthy as a power play than the invasion of Ukraine.

He is using military power to prop up Bashar al-Assad, a vicious dictator who is intentionally slaughtering the Syrian people and helping prolong ISIL’s terror in an attempt to retain power.

And let’s be clear about something: No matter what Putin says, he is not involved in Syria out of an altruistic desire to defeat ISIL. The first airstrikes Russia conducted were in areas where ISIL is not present. They are targeting other moderate opponents of the Assad regime.

Putin is involved for the purpose of keeping Assad, or someone like Assad, in power; keeping Syria as a client-state for Russia; and distracting from his actions in Ukraine.

Even as we must confront Russia in Europe and the Middle East, we need to increase our support to the Russian people. It is important to note that our concerns with Russia are not with them – for it is they who suffer most from Putin’s lies, thievery and repression. Unlike this President, I will speak frankly about who Vladimir Putin is and what his regime represents.

I will increase our efforts to counter Russian propaganda so that the Russian people have access to accurate information. And I will use all the tools at my disposal to sanction those Russian officials involved in human rights abuses, including those who target members of the Russian opposition and kill true Russian patriots like Boris Nemtsov.

As the Obama/Clinton record has shown, the longer we wait to stand strong against Putin’s Russia, the higher the price of our inaction will be.

Sen. Ted Cruz (Tx.):

"America has retreated from the world," Cruz says. "Every bad actor on earth has taken the measure of President Obama and determined that he is no credible threat whatsoever. For the next sixteen months, we are in a Hobbesian state of nature, it is like Lord of the Flies, where the only limit on misconduct and aggression of bad actors is the limit of their own strength."

Gov. Jeb Bush (Fl.):

Bush called Russian President Vladimir Putin’s authorization of airstrikes “outrageous.”

“He’s attacking the Syrian Free Army, the remnants of an army that we [supported] during the time when it actually had strength,” Bush said. “And now instead of us creating a no-fly zone, he’s in fact saying there’s a no-fly zone including American Air Force.”

The former governor said sanctions against Russia should “be on the table.”

“I think we ought to engage with our European allies,” Bush said. “France and Germany both have said they’re prepared to engage militarily as it relates to ISIS and this was an effort to try to stop all that. And I just think it’s wrong. And then on our side, we have Donald Trump saying that refugees need to be sent back. If he’s elected president, he’ll just round them all up and send them back. This is not an America that I believe is the one that will create peace and security.”

Gov. John Kasich (Oh.):

“Russia’s recent military build-up and intervention in Syria are neither intended to defeat ISIS nor to relieve the suffering of Syrian refugees. Mr. Putin’s real goals are quite different: to take military action to rescue Assad’s criminal government from its death and to strengthen Russia’s strategic position in the Eastern Mediterranean. This is unacceptable and must stop.

“The Syrian opposition and three of Syria’s regional neighbors, Turkey, Saudi Arabia and Jordan, insist that the violent actions of Bashar al-Assad’s government against its own people, described by the UN as crimes against humanity, disqualify Assad from any further legitimate claim to rule the country. All that Mr. Putin’s attempts to keep the Assad government alive will therefore achieve is to extend the Syrian people’s suffering. Saudi Arabia has stated that Mr. Putin’s actions in Syria may cause it to intervene militarily in Syria. To prevent further escalation and suffering by civilians and refugees, the U.S. and its regional and West European allies need to establish sanctuary areas in Syria that are protected by ‘no fly zones.’

“With hundreds of millions of dollars in revenue from clandestine oil exports and other illegal activity, increasingly sophisticated arms and equipment and an international network of supporters far superior to any enjoyed by al-Qaeda on 9/11, ISIS poses a serious threat to the U.S. and its allies. This leaves little choice but to act against ISIS immediately, or potentially pay a much higher price later.

“The United States, Iraq, Saudi Arabia, Turkey, Jordan, and the Arab League should deploy a regional coalition of ground troops to defeat al-Qaeda and ISIS in Syria and Iraq. The coalition should be regionally led. It should remain deployed until a transitional council can achieve a regional commitment to a sustainable political solution that will restore peace and security to Syria and Iraq.

“No one should be deluded into thinking that Russian military intervention is a solution to Syria’s problems. Putin seeks to advance Russian interests in the region. Nor should we allow Mr. Putin to use the Syrian crisis to distract attention from his ongoing aggression in Ukraine.

“Now is the time for the United States to provide the moral leadership that it has so far failed to provide. We must act decisively, rally our allies and contribute troops to a regional military coalition in order to put an end to the years of suffering caused by this conflict.”

Sen. Rick Santorum (Pa.):

"I have no problem with the Russians protecting their security," Santorum told CNN's Brooke Baldwin. "Vladimir Putin is acting very rationally."

The Republican presidential candidate says that as president, he would choose take his focus away from Syria to the fight against ISIS in Iraq, since "we have no good options in Syria."

"Our fight is in Iraq, not in Syria," Santorum said. The former Pennsylvania senator advocated for putting boots on the ground in Iraq, leaving Putin and Syrian President Bashar al-Assad to handle ISIS in Syria.

Sen. Lindsey Graham (S.C.):

“The Iranian-Russian alliance is bad news for us because he wants to prop up Assad, who is a proxy of Russia and a puppet of Iran. Why is that bad for us? It means that Syria never heals itself and the war continues to go on. The Sunni radical Islamists like ISIL and Al Nusra now have a recruiting tool. Assad’s their biggest enemy. He’s an Alawite sponsored by Iran, so keeping Assad in power is bad news for us.”

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“This is a complete shift of power. If you’re an Arab, this is a bad day for you because the war in Syria involves two things that you don’t like, ISIL, which is coming after you and your kingdom and your government, and Assad, which is a proxy of your mortal enemy, the Iranians. So now, they have more influence in your back yard than ever. From an American point of view, it means the war continues. The Syrians will not accept Assad as their leader, so they’ll keep fighting and that means ISIL actually gets stronger, not weaker, more likely to attack our homeland. So this relationship between Iran, Syria, Iraq, and Russia is just a very bad deal for the region and eventually, our homeland.”

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“If Putin and Iran, together, run Syria it means the war in Syria never ends. It means the refugees continue to flow. It means that our allies, the King of Jordan and our friends in Lebanon are at risk. It means ISIL gets stronger, but they also have a recruiting tool for the ages. It means the Syrian people never reconcile themselves. The war goes on and Syria begins to spread and take down the entire mid-east.”

Gov. Chris Christie (N.J.):

"For 40 years, we've kept Russia out of the Middle East," Christie said during an appearance on "Fox & Friends." "And now this president has let them back in. They're teaming with Iran — our 'good friends,' Iran. We're in the honeymoon period of this (nuclear) agreement with Iran, suppossedly and now they're teaming with Russia to try to dominate the Middle East. ... This is the beginning of Russia trying to replace America as the dominant power in the Middle East."

Sen. Rand Paul (Ky.):

"There may be no good guys in this war. You have ISIS on one side and Assad on the other. Really, part of the problem is ourselves, Saudi Arabia, and Qatar poured millions of tons of weapons into that civil war. That pushed Assad back and allowed ISIS to grow.

"Remember, only a year or two ago, President Obama, Hillary Clinton and many Republicans wanted to bomb Assad.

"I think had we done that, ISIS may well now be in control of all Syria. We need to think before we act and understand that intervention doesn't always acheive the intended consequences."

Virginia Gov. Jim Gilmore:

There have not been any publicly available statements from Arkansas Gov. Mike Huckabee, Lousiana Gov. Bobby Jindal and New York Gov. George Pataki.