The US Holocaust Memorial Museum reopened its doors Friday to crowds of visitors who came to pay tribute to the latest victim of the racial intolerance the institution is dedicated to opposing, and to call for its work to continue despite the threats it faces. Those who visited the museum, which was shut the day before to honor Stephen Johns, the security guard killed by a white supremacist on Wednesday, called it a repudiation of the hatred James von Brunn showed when he opened fire at the building dedicated to the memory of those who died at the hands of the Nazis. "It's important to come back, because if you don't, they win," 17-year-old Tammi Miller, who was evacuated from the museum during Wednesday's shooting, told The Washington Post. She and her family returned Friday to finish their tour. According to the Post, Sara Bloomfield, the museum's director, said Friday witnessed at least as many visitors as a normal day, if not more. She also praised those who came for performing "an act of defiance," which she described as an illustration "of what this country is all about." On Saturday the museum announced it had set up a fund to benefit the Johns family, which comes on top of a similar fund set up by the American Jewish Committee on Thursday. Johns, 39, a private guard who had worked at the museum for six years, left behind a wife and an 11-year-old son from a previous marriage. His widow, who had recently celebrated their one-year anniversary, released a note Friday saying, "Steve was my husband and my best friend. He was my everything." Johns was described by friends and coworkers as exceedingly kind and courteous. He left that impression on museum-goers too, including Dianne Romano, who Johns helped shortly before the shooting. "He was so nice to us when we came in, telling us where to go," Romano recalled. Johns apparently opened the door for the 88-year-old von Brunn, according to authorities. Though it is not clear whether von Brunn, who was hit by return fire and has remained in critical condition, targeted Johns because he was AfricanAmerican, his writings - including a note police found in the car he parked near the museum - make clear that he despised blacks as well as Jews. "The Holocaust is a lie," the note said. "[US President Barack] Obama was created by Jews. Obama does what his Jew owners tell him to do. Jews captured America's money. Jews control the mass media." Analysts have reportedly seen an increase in extremist threats with the election of the country's first black president and the economic downturn, and are warning that a spate of similar attacks could be in store. "I believe we are headed for an unprecedented level of conflict and racial turmoil," said Carol Swain, a Vanderbilt University expert on white nationalism. Former FBI agent Danny Coulson said federal agents have increased their monitoring of white supremacist groups since Obama's election and have noticed increased chatter and membership. "These neo-Nazi groups have been laying in the weeds for a long time," he said. "Then you have a president who comes in who's an African American and they hate that." An April intelligence assessment by the Department of Homeland Security said right-wing extremists could use the troubled economy and Obama's election to recruit members. Concerned von Brunn's actions could also be used to enlist followers to an ideology fostering "sadness and anguish," his son released a statement to ABC News urging that not happen. "For the extremists who believe my father is a hero: it is imperative you understand what he did was an act of cowardice," Erik von Brunn wrote. "To physically force your beliefs onto others with violence is not brave, but bullying. Doing so only serves to prove how weak those beliefs are." The killer's son went on to say, "His actions have undermined your 'movement,' and strengthened the resistance against your cause." On a more personal level, he condemned his father's actions and the pain and suffering they have long wrought. "His views consumed him, and in doing so, not only destroyed his life, but destroyed our family and ruined our lives as well. For a long time, I believed this was our family's cross to bear. Now, it is not only my families' lives that are in shambles, but those who were directly affected by his actions; especially the family of Mr. Johns, who bravely sacrificed his life to stop my father." He added, "I cannot express enough how deeply sorry I am it was Mr. Johns, and not my father who lost [his] life." AP contributed to this report.