Who is Jeh Johnson?

The former general counsel for the Pentagon became the Secretary of Homeland Security in December, leading a department that includes 22 agencies that are supposed to prevent attacks like what happened on Sept. 11, 2001.

In his Pentagon role, Johnson, 56, was one of the key figures in the repeal of “Don’t Ask, Don’t Tell.”

Why is he on theGrio’s 100?

Johnson’s appointment is part of a historic group of African-Americans who have risen to key national security posts under President Obama.

In a statement, Obama praised the Senate for confirming Johnson, calling him “a critical member of my national security team.”

“And he helped to shape some of our most successful national security policies and strategies,” the president added.

Along with the first-ever black commander-in-chief and chief law enforcement officer (Attorney General Eric Holder), National Security Adviser Susan Rice and now Johnson all play very key roles in defense policy.

What’s next for Johnson?

The next three years are likely to be intense for Johnson, who is running a complicated agency that is tasked with being involved in both preventing terrorism and helping Americans recover from natural disasters.