Democratic presidential nominee Hillary Clinton on Friday announced Virginia Sen. Tim Kaine as her running mate, creating a formidable foreign policy tandem in a year when Republicans hope to own national security as their issue.

Kaine, 58, serves on the Senate Foreign Relations, Armed Services and Budget committees, where he has been both an ally and a critic of the White House in the war on the Islamic State. Kaine has faulted both the administration and Congress on the lack of a new authorization of the use of military force for the president.

In a campaign where Republican nominee Donald Trump and his party have made immigration and national security key issues, Democrats now have a ticket with two heavyweights, Kaine, and Clinton, the former secretary of state.

Clinton, after a methodical search, made the public announcement in the battleground state of Florida. Kaine speaks fluent Spanish and last week rallied with Clinton in Virginia, where he announced: "Estamos listos para Hillary!" or "We are ready for Hillary!" Kaine had been a strong supporter of hers.

I'm thrilled to announce my running mate, @TimKaine, a man who's devoted his life to fighting for others. -H pic.twitter.com/lTVyfztE5Z — Hillary Clinton (@HillaryClinton) July 23, 2016

Kaine was in 2008 short-listed as Obama's running mate but he has not been above criticizing the Obama administration's foreign policy strategy, and at an Oct. 29, breakfast with reporters he called it "reactive." Kaine, at the time, said he said the U.S. should be shoring up democracies, have tailored approaches to each authoritarian regime and work to defeat the non-states militarily and otherwise.

Just got off the phone with Hillary. I’m honored to be her running mate. Can’t wait to hit the trail tomorrow in Miami! — Senator Tim Kaine (@timkaine) July 23, 2016

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Like Clinton, Kaine favors the creation of humanitarian safe zones in the war against the Islamic State, though the idea has yet to gain traction in Congress.

"It's going to be up to her to paint the picture of how she will look at this challenging situation," Kaine said of Clinton at the time. "I think she's probably better equipped than anyone else running for president."

Kaine also favors modernizing the nation's nuclear triad and earlier this month was among 14 senators from both parties who signed a letter to Defense Secretary Ash Carter asking him to reaffirm his commitment. Lawmakers have questioned whether the Obama administration is backing away from support for the nuclear modernization program, but the next president is expected to set their own priorities.

A St. Paul, Minnesota, native, Kaine served as Virginia's governor from 2006 to 2010 and was elected to the Senate in 2012. He earned a law degree from Harvard Law School and was a lecturer at the University of Richmond School of Law.

Email: jgould@defensenews.com

Twitter: @reporterjoe