Islamic extremists beheaded a freelance reporter, James Foley. Another American journalist is next, they warned. In Iran, Jason Rezaian, a reporter for The Washington Post, was snatched by men waving an arrest warrant in late July. He has not been heard from since. In Afghanistan, Matthew Rosenberg, a reporter for The New York Times, was ordered expelled from the country because government officials did not like his stories. In America, journalists have been hit with tear gas and held by the police, with little explanation, while covering protests in Ferguson, Mo. At the Justice Department, prosecutors have aggressively prosecuted leaks to journalists and employed eavesdropping techniques that have chilled the relationship between reporters and their sources. In a series of interviews on Wednesday, reporters, editors and those who monitor the freedom of the press described a harsh environment for reporters both at home and abroad, complicated by changes in the way that journalists work, and a change in the way they are viewed by both governments, and the public.