Inside the Beltway
"Inside the Beltway" is an American idiom used to characterize matters that are, or seem to be, important primarily to officials of the U.S. federal government, to its contractors and lobbyists, and to the corporate media who cover them—as opposed to the interests and priorities of the general U.S. population.
The Beltway refers to Interstate 495, the Capital Beltway, a circumferential highway (beltway) that has encircled Washington, D.C. (the capital of the United States) since 1964. Some speakers of American English now employ the word as a metonym for federal government insiders (cf. Beltway bandits).
Geographically, Inside the Beltway describes Washington, D.C. and those sections of Maryland and Virginia that lie within the perimeter of the Capital Beltway. Specifically, this includes Arlington County, Virginia; the city of Falls Church, Virginia; most of the city of Alexandria, Virginia; and portions of Montgomery County, Maryland, Prince George's County, Maryland, and Fairfax County, Virginia.
In the White House of Richard M. Nixon, it was said that Watergate would become serious only if it 'got outside the Washington Beltway', if the depths of the disgrace were understood by the American people. In 1974, the truth of Watergate flooded the country, and the Nixon presidency ended.
It can be said that the myriad doubts about the Warren Commission's findings in the death of President Kennedy represent a reverse situation. The doubts would never be taken seriously until they were inside the Beltway, in the halls of Congress, the courts and the White House.—Nicholas M. Horrock, (October 12, 1975) The New York Times: p. 230.