President Obama announced Tuesday he plans to nominate Vice Adm. Peter V. Neffenger, the current vice commandant of the Coast Guard, to lead the Transportation Security Administration. 

Neffenger, if confirmed, would take over an agency scrambling to address the increasingly complex threat posed by terrorists being trained by the Islamic State and other groups -- some of whom have western passports and may try to return to their home countries. 

"The talent and expertise Vice Admiral Neffenger brings to his new role after more than three decades at the U.S. Coast Guard will be valuable to this Administration's efforts to strengthen transportation security," Obama said in a written statement. "He has been a recognized leader in the face of our nation's important challenges, and I am grateful for his service. I look forward to working with him in the months ahead." 

Neffenger, if confirmed, would replace acting TSA head Mevlin Carraway, who took over after John Pistole retired for a job in academia. 

Neffenger has served as vice commandant in the Coast Guard since May 2014. He also was deputy national incident commander for the Deepwater Horizon oil spill off the Gulf Coast. 

The TSA, which often has an adversarial relationship with the traveling public, nevertheless is at the center of the effort to prevent foreign fighters training with groups like ISIS in the Middle East from trying to return and do harm. The agency is also faced with the challenge of how to prevent a terrorist from boarding a plane with a bomb that contains no metal parts and isn't detectable through normal screening. 

Pistole warned last year that an Al Qaeda cell in Syria known as the Khorasan Group had been researching and testing improvised explosive devices designed to elude airport security and represents "a clear and present danger" to commercial flights to Europe and the United States. 

Pistole, TSA's administrator for four and a half years, instituted a "risk-based" security philosophy that has enabled the agency to move passengers deemed to be low risk through airport screening more quickly and significantly reduced complaints.  The Trusted Traveler and PreCheck programs are used by 5 million passengers per week at 120 U.S. airports, according to the agency. 

TSA has a workforce of over 60,000 employees and security operations at more than 450 airports throughout the United States. 

The Associated Press contributed to this report.