Robert C. O'Brien

George W. Bush and Obama administrations

O'Brien was nominated by President George W. Bush as the U.S. alternate representative to the 60th session of the United Nations General Assembly during 2005–06.

O'Brien was co-chairman of the U.S. Department of State's Public-Private Partnership for Justice Reform in Afghanistan, launched in December 2007, which "promoted the rule of law" in Afghanistan by training judges, prosecutors, and defense attorneys. He continued this role during the first term of the Obama administration.

On July 31, 2008, President Bush announced his intention to appoint O'Brien to serve in his administration as a member of the Cultural Property Advisory Committee, an advisory committee on issues involving antiquities and cultural matters, for the remainder of a three-year term which expired on April 25, 2011.

Mitt Romney 2012 campaign

In October 2011, O'Brien was named to Mitt Romney's advisory team as co-chair of the International Organizations Work Group.

2016 presidential election

Later, in May 2015, he became an adviser on foreign policy and national security affairs for Wisconsin Governor Scott Walker's presidential campaign. After Walker left the race, O'Brien advised Ted Cruz's campaign. During the time he advised Cruz's presidential campaign, he said: "It's clear that Vladimir Putin just doesn't like [Hillary Clinton], and is going to do what he can to help Donald Trump."

First Trump administration (2017–2019)

In 2017, O'Brien was under consideration by the Donald Trump administration to serve as secretary of the navy. The Orange County Register editorial board endorsed O'Brien to serve in this position. Later in the administration, O'Brien advocated publicly for a larger Navy and visited several U.S. shipyards.

From May 25, 2018 to October 3, 2019, O'Brien served as the special presidential envoy for hostage affairs. He was given the rank of ambassador one year after his appointment. As envoy for hostage affairs, O'Brien attended the trial of the American rapper ASAP Rocky, on assault charges, in Stockholm, Sweden, telling reporters, "The president sent me here, so it's totally appropriate. I also help free people that are held by governments, so unjustly detained Americans." O'Brien had written the Swedish government warning of "negative consequences" if the case was not resolved. The Swedish government and court rejected political pressure in the case, citing rule-of-law principles; the rapper was ultimately convicted of assault, and sentenced to time served.

In 2018, as envoy for hostage affairs, O'Brien helped obtain the release of American pastor Andrew Brunson, who had been held prisoner for two years in Turkey, raising U.S.-Turkish tensions. O'Brien was also involved in obtaining the release of Danny Burch, an American oil worker held in Yemen for a year, and who ultimately received an Oval Office meeting with President Trump. In June 2022, French President Emmanuel Macron awarded O'Brien the rank of chevalier in the Legion d'honneur, in part for his assistance in helping to rescue two French hostages kidnapped abroad.