Former Defense Secretary Donald Rumsfeld, in an interview with TODAY's Matt Lauer, addressed criticism by former President George H.W. Bush and weighed in on the candidacy of GOP front-runner Donald Trump.

"I see someone who has a touched a nerve in our country," Rumsfeld said Monday, referring to Trump.

Rumsfeld, who served under President George W. Bush for most of both terms, has stayed quiet about the current slate of Republican presidential candidates but said Trump has "caused people to respond in a way that most politicians have not been able to do."

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The former congressman also directly addressed criticism by the senior Bush in his authorized biography last fall. President George H.W. Bush called Rumsfeld an “arrogant fellow” who served “the president badly."

At the time, Rumsfeld fired back, attributing the harsh words on the age of the elder Bush, who is 91.

On TODAY, Rumsfeld said he and the elder Bush never had a close relationship.

"We were never close. It didn't surprise me." -Donald Rumsfeld reacts to criticism from Bush 41 in Meacham book https://t.co/bXbirziosw — TODAY (@TODAYshow) January 25, 2016

"We were never close. He was kind of 'to the manor born' and I wasn't," he said, adding that he also questioned the motivation and timing of the criticism.

“I didn’t think it was complimentary of his son, George W. Bush, and I didn’t think it was very helpful to his other son, who's running for president, so I thought it was a strange thing for him to be doing," Rumsfeld said, who also took a stab at why Jeb Bush's campaign had failed to catch fire.

"I suppose there are some people that are uncomfortable with a dynasty," he said.

Rumsfeld later discussed a new gaming app he recently launched called "Churchill Solitaire," a variation of the traditional card game that uses two decks of cards instead of one.

"It's vastly more complex and requires a strategic thinking," said Rumsfeld, who learned the game in the 1970s from a friend who was taught by former British Prime Minister Winston Churchill.

All profits from the app will go to military charities that aid servicemen and their families, Rumsfeld said.

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