( CNN ) -- A child was killed Friday because that child went to school . The shooting Friday at a high school in Marysville , Washington -- just miles from my home in Seattle -- is a tragedy on two levels . First , most profoundly , two people are dead , four others wounded , and the parents , relatives , friends , teachers and classmates of the shooter and his victims have had their lives grievously changed . But this is not the first shooting in and around schools and colleges in America since the most infamous shooting at Sandy Hook . There have been many . ( The exact numbers differ depending on how you count . ) The other tragedy , then , is that gun violence -- in schools , in workplaces and across our communities -- has become virtually normal in America . It should not be . It can not be . It is not normal , in a civilized nation , to have over 30,000 gun deaths a year . It is not normal , in a civilized nation , to expect educators and parents and first responders to have plans at the ready for a shooting at their school . It is not normal , in a civilized nation , to assert that the best solution to gun violence is for more people to have more access to more guns . So the question we must confront is : Are we a civilized nation ? Earlier this week , I listened to a BBC correspondent open a report on the shootings in Ottawa , Ontario , by saying : `` In a scene reminiscent of America ... . '' That is not the kind of exceptionalism America should be proud of . Though the Ebola crisis makes us rightly careful about using the word `` epidemic , '' it is no overstatement to say that the United States has been in a years-long epidemic of gun violence . The sheer volume of homicides , accidental killings , suicides and merely disabling injuries is staggering . The number , both in absolute and per capita terms , exceeds by many times that of any other developed country on Earth . What also makes this an epidemic is that it is contagious . The more it spreads , the more it spreads . The more that a minority of citizens block prevention and treatment , the less effective prevention and treatment become for all . To put it bluntly , gun violence is orders of magnitude more deadly to Americans than Ebola . So , what do we do about the public health crisis of gun violence ? We have to turn to both law and norms . Many gun-rights absolutists respond to the death and mayhem of a Marysville or a Sandy Hook by saying that a particular gun law -- say , background checks for gun purchases -- would n't have prevented that tragedy . But when someone driving under the speed limit dies in a car wreck , we do n't throw out speed limits and declare them an ineffective burden . We recognize that speed limits and seat belt laws are part of a grown-up system of rules that reduce the overall likelihood of traffic fatalities . In precisely the same way , a requirement of background checks for gun purchases reduces the overall likelihood that people will die of gun violence . That 's why in the state of Washington , I 've been working with other citizens to secure passage of a ballot initiative that will create such background checks . And it 's why that measure seems to most people here not like tyranny but like common sense . The challenge extends beyond lawmaking to norm-setting . The coalition of parents , faith leaders , educators , businesspeople and others in Washington who are uniting behind background checks do so in the name of a core social norm : responsibility . All our American rights -- and particularly Second Amendment rights -- come with responsibilities . The responsibility , for instance , to minimize the danger inherently created by the circulation of weapons that can kill en masse . The responsibility to foster a culture of safety , especially for our youth . When middle-aged `` open-carry '' activists walk into Kroger with semi-automatic rifles slung over their shoulders , they are n't exercising their rights with an ethic of responsibility . They 're trying to intimidate their way to respect and esteem . They 're acting out , demanding attention and rejecting curbs on their desires . That 's not being a citizen . It 's being a toddler . We the people get to decide whether that 's normal . Whether it 's acceptable or laughable to brandish firearms in the produce aisle . Whether it 's tolerable or disgraceful that we average more than one school shooting a week now . Laws like background checks can help set a tone for what 's OK . But ultimately , with our family and friends and neighbors , each one of us must decide what kind of civilization we expect in the United States . Somebody 's child was killed Friday because that child went to school . Somebody has to do something about it . In ways full of both risk and responsibility , you are that somebody .
Eric Liu : A child was killed because he went to school in Marysville , Washington , today . Liu : Steady stream of shootings makes them virtually normal . Is this `` American exceptionalism '' ? It 's contagious epidemic . Comment: Liu : We the people must set tone , standards , with laws , norms . It 's our responsibility .