So far as we can tell, Congress has acceded to nearly every proposal made by security experts to keep the Capitol Complex safer — except one. And, thankfully, it appears that lawmakers will continue to oppose construction of a White House-style fence around the Congressional perimeter, even if Capitol Police Chief Terrance Gainer has changed his mind on the subject.

Every time the idea has been broached in the past — before last Wednesday, at least — Gainer has said virtually the same thing: Yes, if security decisions were made in a vacuum, Congress might erect a fence around the Hill and turn away tourists, too. “But I wouldn’t support that. I don’t support the notion that you put brick walls around this place,” he said in 2003, echoing comments in 2002. But last week, at a hearing of the Senate Appropriations subcommittee on the legislative branch, Gainer changed his tune and spoke positively about the fence idea.

His reasoning is that existing and planned security measures — bollards, extra police personnel at entrances, magnetometers, blocked-off streets, mylar on windows and the Congressional Visitor Center — will protect against vehicle bombs, but maybe not (or at least not adequately) against individual suicide bombers. “It is our concern that small types of explosives … are still a danger,” he said.

Gainer quoted from a 2003 report issued by the General Accounting Office to the effect that “an aesthetically pleasing perimeter security fence could be constructed around the Capitol Building grounds. This would markedly increase security …”

Fortunately, most Congressional appropriators and authorizers are united in having none of it, and for the same reason that the fence idea has been blocked ever since it was raised in 1985: Congress is the people’s branch of government and building a fence around it inherently says: Keep Out. “Most Americans would rebel at the thought of the Capitol being fenced in,” said Sen. Ben Nighthorse Campbell (R-Colo.), chairman of the Senate subcommittee.

Similarly, Rep. John Larson (D-Conn.), ranking member of the House Administration Committee, said, “There are a number of Members here that are concerned about security and equal amount concerned about keeping the seat of government open to the public.” More pungently, Rep. Jim Moran (D-Va.), the ranking member of the House Appropriations subcommittee on the legislative branch, said, “I don’t think this is a flag that’s going to be up for long.”

Moran, who has a tendency to make intemperate remarks about Israel, said that “Chief Gainer has been spending too much time with [Israeli Prime Minister Ariel] Sharon.” But there is a valid point here. Israel is building a fence to keep Palestinians out because it has seen hundreds of its citizens killed by suicide bombers mingling with crowds. The United States, mercifully, has seen none. The U.S. Capitol ought not be fenced off from the American people as a pre-emptive measure.