(CNN) – Conservative heavyweights, some of whom might launch White House campaigns, contend a weak foreign policy under President Barack Obama emboldened Russia to intervene militarily in Ukraine.
The European crisis wasn't at the top of the agenda at the annual Conservative Political Action Conference, but a number of speakers put it at the top of theirs.
They said the entire affair illustrates an unconvincing American presence on an international stage.
"Putin would not be acting with this level of aggression if it were not for the consistent weakness and appeasement of our enemies of President Obama," Sen. Ted Cruz of Texas told reporters.
Sen. Marco Rubio of Florida called Russia's intervention in Crimea a "critical moment in our nation's history" before slamming Obama for relying on his global star power to influence international relations.
"I don't like to make these issues of national security partisan because it's important that our country be united in moments like this but we cannot ignore that the flawed foreign policy of the last few years has brought us to this stage," Rubio said.
As Russia tries to exert influence in the region, Rubio warned of leaders like Putin gaining further traction in their efforts to expand power.
Louisiana Gov. Bobby Jindal took a less measured approach to criticizing Obama with regard to Russia. He flat out questioned the President's intelligence.
"We have long thought and said this President is a smart man. It may be time to revisit that assumption," he said.
Obama "doesn't understand that a weak America leads to instability" and "who doesn't seem to understand that our allies, our enemies alike need and want a strong America," he said.
New Jersey Gov. Chris Christie did not mention Ukraine in his address to the political gathering but did allude to America's global standing as seen through a conservative Republican lens.
"We need to make sure that we say we are for America being a leader in the world. And we are for a strong national defense, not one that allows other countries to run us over all over the world," he said to applause.
Many Republicans have been outspoken on Obama administration plans to scale back the military in an era of budget austerity.
John Bolton, a senior fellow at the conservative American Enterprise Institute and former U.S. ambassador to the United Nations, said "our biggest national security crisis is Barack Obama."
"We're not going to get peace through strength because we're not devoting the budget to it. But we're not going to get peace through weakness either. We're gonna get what we see today in the Ukraine where Vladimir Putin has a strategy and Obama has nothing, where Putin has a growing defense budget, and ours is shrinking," he said.
The administration is pursuing a diplomatic strategy along with European allies to remedy the crisis, and has threatened economic and other sanctions if the matter cannot be resolved.
Obama has called Putin's incursion into Ukraine a violation of international law, and says the Ukrainian people should determine their own destiny.