Question: "A More Perfect Union" is the name of a speech delivered by then Senator and future President Barack Obama on which date, Obama was responding to a spike in the attention paid to controversial remarks made by the Reverend Jeremiah Wright, his former pastor and, until shortly before the speech, a participant in his campaign?
Context: Jeremiah Alvesta Wright Jr. (called Jerry; born September 22, 1941) is a pastor emeritus of Trinity United Church of Christ in Chicago, with a congregation exceeding 6,000.  In early 2008, Wright retired after 36 years as the Senior Pastor and no longer has daily responsibilities at the church.  Following retirement, Wright's beliefs and preaching were scrutinized when segments of his sermons were publicized in connection with the presidential campaign of Barack Obama.  Obama addressed the issues raised by the Wright controversy in his speech entitled "A More Perfect Union". "A More Perfect Union" is the name of a speech delivered by then Senator and future President Barack Obama on March 18, 2008 in the course of the contest for the 2008 Democratic Party presidential nomination.  Speaking before an audience at the National Constitution Center in Philadelphia, Pennsylvania, Obama was responding to a spike in the attention paid to controversial remarks made by the Reverend Jeremiah Wright, his former pastor and, until shortly before the speech, a participant in his campaign.  Obama framed his response in terms of the broader issue of race in the United States.  The speech's title was taken from the Preamble to the United States Constitution. The Jeremiah Wright controversy gained national attention in the United States, in March 2008 when ABC News, after reviewing dozens of U.S. Presidential candidate Barack Obama's pastor Jeremiah Wright's sermons, excerpted parts which were subject to intense media scrutiny.  Wright is a retired senior pastor of Trinity United Church of Christ in Chicago and former pastor of President Obama.  Obama denounced the statements in question, but critics continued to press the issue of his relationship with Wright.  In response to this, he gave a speech titled "A More Perfect Union", in which he sought to place Wright's comments in a historical and sociological context.  In the speech, Obama again denounced Wright's remarks, but did not disown him as a person.  The controversy began to fade, but was renewed in late April when Wright made a series of media appearances, including an interview on "Bill Moyers Journal", a speech at the NAACP, and a speech at the National Press Club.  After the last of these, Obama spoke more forcefully against his former pastor, saying that he was "outraged" and "saddened" by his behavior, and in May he resigned his membership in the church. Harris Llewellyn Wofford Jr. (born April 9, 1926) is an American attorney and Democratic Party politician who represented Pennsylvania in the United States Senate from 1991 to 1995.  A noted advocate of national service and volunteering, Wofford was also the fifth president of Bryn Mawr College from 1970 to 1978, served as Chairman of the Pennsylvania Democratic Party in 1986, as Pennsylvania Secretary of Labor and Industry in the cabinet of Governor Robert P. Casey from 1987 to 1991 and was a surrogate for Barack Obama's 2008 presidential campaign.  He introduced Obama in Philadelphia at the National Constitution Center before Obama's speech on race in America, "A More Perfect Union". Perry Noble (born June 24, 1971) is an American preacher, author, and the former senior pastor at NewSpring Church, a megachurch located in Anderson, South Carolina.  His weekly sermons were watched by over 32,000 people at 11 satellite campuses across the state of South Carolina with an additional 7,200 viewers tuned in weekly via online live stream.  He has gained notability as the senior pastor at the largest church in the South Carolina Baptist Convention and second fastest-growing church in the United States.  Noble gained notoriety for controversial remarks made regarding the Ten Commandments during a Christmas Eve service at his church, as well as his forced removal from the church as pastor. Juan Verde Suárez (born July 7, 1971) is a business and social entrepreneur who worked on the political campaigns of Senator Ted Kennedy, President Bill Clinton, Vice President Al Gore, Senator John Kerry, and Secretary of State Hillary Clinton, besides serving as International Co-Chair for the reelection campaign of President Barack Obama in 2012.  In addition to developing and directing a strategy designed to mobilize millions of American citizens residing outside of the United States, Mr. Verde serves as an advisor to President Obama on international trade, the Hispanic vote as well as sustainability related issues.  Mr. Verde was appointed by President Barack Obama as Deputy Assistant Secretary for Europe and Eurasia at the US Department of Commerce where he served until 2011. Shefali Razdan Duggal (born November 22, 1971) is an Indian-born American Democratic political activist in San Francisco who is a Presidential Appointee to President Barack Obama to the United States Holocaust Memorial Council, which supervises the United States Holocaust Memorial Museum, for a term expiring in January 2018.  She was an active fundraiser for the Barack Obama election campaign in 2008 where she was a Trustee for the DNC South Asian American Leadership Council.  She focused on South Asian and Young Professional outreach, co-hosting a number of fundraising events for both the Senator and his surrogates.  She was a member of President Barack Obama's National Finance Committee for his reelection campaign in 2012, a co-chair for Obama Victory Trustees, and the Northern California Finance Committee.  She worked on the Massachusetts Democratic Party, New Hampshire Democratic Party, and Senators Ted Kennedy and Dianne Feinstein.  She also worked on the Al Gore presidential campaign in 2000, and Hillary Clinton’s presidential campaign in 2008. "You didn't build that" is a phrase from an 2012 election campaign speech delivered by former United States President Barack Obama on July 13, 2012, in Roanoke, Virginia.  The sentence "If you've got a business – you didn't build that" was publicized by his political opponents during the 2012 presidential campaign, as an attack by Obama on business and entrepreneurs.  The Obama campaign responded that the criticisms were taking the phrase out of context, and the word "that" in the phrase was referring to the construction of "roads and bridges" in the previous sentence. Zeituni Onyango ( ; May 29, 1952 – April 7, 2014) was known as the half-aunt of United States President Barack Obama; she was born into the Luo tribe in Kenya.  Born during the British rule of the Protectorate of Kenya, Onyango was the half-sister of Barack Obama, Sr., father to the president.  The younger Obama refers to her as "Aunti Zeituni" in his 1995 memoir, "Dreams from My Father".  In 2002 she had applied for political asylum in the United States but was denied.  She became notable when her case was leaked in the final days of the 2008 U.S. presidential campaign in which Barack Obama was the Democratic candidate, attracting international media attention. "A New Beginning" is the name of a speech delivered by United States President Barack Obama on 4 June 2009, from the Major Reception Hall at Cairo University in Egypt.  Al-Azhar University co-hosted the event.  The speech honors a promise Obama made during his presidential campaign to give a major address to Muslims from a Muslim capital during his first few months as president.
Answer: March 18, 2008