DAWN WALTON Globe and Mail Update Calgary — Former U.S. president George W. Bush defended his decision to invade Iraq, said “risk takers,” not government are needed to salvage the world economy and offered his advice to current U.S. administration during a luncheon speech in Calgary. In his first public address since U.S. President Barack Obama moved into the White House, Mr. Bush was greeted with a standing ovation when he took the podium by close to 2,000 guests who paid $4,000 per table. “This is my maiden voyage. My first speech since I was the president of the United...