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Just two days after smiling for a mugshot, Texas Gov. Rick Perry took his message to conservatives in Washington, D.C., quickly turning from talk of his indictment to weighing in on the threat ISIS poses to the United States.

In a speech at the Heritage Foundation, a conservative think tank, Perry connected the border crisis to ISIS, warning that terror groups could cross the border between the U.S. and Mexico.

"I think it's a very real possibility they may have already used that," Perry said, referring to the border. "We have a serious issue facing this country and the security of our citizens. We need to be very vigilant. We have to be using every authority that we have."

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The Texas governor said the recent events in Syria and Iraq should put the country on alert for a potential terrorist attack and argued the U.S. must respond in a decisive manner to root out ISIS.

"They should have us thinking about a possibility of another terrorist attack in this country," Perry said. "We have come to one of those moments where American action will be decisive and inaction will be consequential."

Perry called for more forceful action in Iraq to fight ISIS, including additional airstrikes, an increase in special forces and offering intelligence assistance. Asked whether the U.S should send combat troops into Iraq, Perry said it would be irresponsible to reveal any strategy to the enemy.

"I think all your options have to be open," he said.

Perry rallied conservatives to work to elect Republicans this cycle, saying the midterm election will be the last opportunity to "pass judgment on the Obama presidency."

"And something tells me he's not going to like it," he added.

The Texas governor's trip to DC comes less than a week after he was indicted on two felony counts of abuse of power for threatening to veto funding for the state's public integrity unit if District Attorney Rosemary Lehmberg refused to resign following a DWI conviction in 2013.

"I am very confident in my case and I can assure you I will fight this attack on our system of government," Perry told the group of conservatives. "I aim to defend our constitution and stand up for the rule of law in the state of Texas."

The governor's office said Perry's campaign fund will pay for further legal bills relating to the indictment.

"This is an assault on the Constitution," Lucy Nashed, a spokesperson for Perry, said. "We don't want it to be an assault on the taxpayers as well."

Perry pled not guilty to the charges on Wednesday and waived his arraignment, which will take place on Friday. Instead, Perry will head to New Hampshire for the weekend where he is set to do a half dozen events, including several with the New Hampshire Republican Party. Next week, Perry will head to South Carolina for the Texas A&M game against the University of South Carolina, where he will headline a tailgate to benefit the Republican Party of South Carolina.