In response to strong criticism from Senate Majority Leader Harry ReidHarry ReidThe Memo: Trump pulls off a stone-cold stunner The Memo: Ending DACA a risky move for Trump Manchin pressed from both sides in reelection fight MORE’s office, Sen. Marco RubioMarco Antonio RubioOvernight Defense: Senate passes 0B defense bill | 3,000 US troops heading to Afghanistan | Two more Navy officials fired over ship collisions Senate passes 0B defense bill Trump bets base will stick with him on immigration MORE (R-Fla.) defended his proposal to authorize President Obama to take action to remove Libyan dictator Moammar Gadhafi from power.

In a letter to Reid, Rubio argued that the only way to protect Americans was to depose Gadhafi.

"The reality is that the U.S. has attacked a brutal dictator with a long history of brazen support for terrorism against Americans," Rubio wrote Thursday night. "We have attacked someone who less than a decade ago was on the verge of acquiring nuclear weapons. If he survives this international effort against him and remains in power, he will be emboldened and angry, and he will once again act against America’s interests."

The back and forth between Rubio and Reid comes a day after Rubio sent a letter to the Senate majority and minority leaders proposing the Senate pass a bipartisan resolution authorizing the president to remove Gadhafi from power.

Earlier Thursday, Reid spokesman Jon Summers said that Rubio's proposal was "oblivious" and would prove costly both economically and in terms of American lives.

Currently the U.S. and NATO are enforcing a United Nations Security Council-mandated no-fly zone resolution over Libya and have been attacking Libyan military targets loyal to Gadhafi.

The stated mission of the U.S. has been to protect Libyan civilians from Gadhafi military forces but not to attack Gadhafi directly. Obama has said the goal is to give Libyan rebels the opportunity to gain enough strength to oust Gadhafi themselves. Still, Obama and other American officials have called for Gadhafi to step down from power.

On Wednesday, media outlets reported that Obama had authorized covert CIA missions to aid to Libyan rebels. In response, administration officials reiterated that it was not directly supporting Libyan rebel forces and had no American military forces on the ground in Libya.

Read Rubio's letter below:

3.31.11 Rubio Letter to Reid (Libya)