Between 1900 and 2018, there have been at least 146 protest marches and rallies, gatherings of people to express their social and political views, in Washington, D.C. It is a time-honored American way of making sure that the government "hears" the people, their passion and their political aspirations. The First Amendment allows this kind of speech, and the government protects it.
Now we have another protest brewing, the national March for Our Lives, which is being led by students. This First Amendment display of complaint is to protest the use of the Second Amendment to protect the widespread availability of military-style weapons on American streets.
It's difficult to tell exactly what is driving the student anti-gun demonstrations that are taking place all across the country: It may, of course, be the actions of the most recent shooting at Marjory Stoneman Douglas High School in Parkland, Florida, that left 14 of their classmates and three of the school's staff members dead and another 14 of them wounded.