The independence of the Western Hemisphere is challenged as much by forces within as by those from without, declared W. Barton Leach, professor of Law, as the opening speaker at the three-day session of the League of Women Voters' School of Foreign Affairs at Radcliffe yesterday.

To the accompaniment of clicking knitting needles, Leach attacked both Charles A. and Anne Lindbergh for their isolationist stand. "Lindbergh is Maginot-minded," he said. "He thinks of American defense only in terms of the Atlantic Ocean and 20,000,000 men of military age."

"England can be beaten, and if she is it will be in the next six months," Leach stated. "There is reason to hope that an invasion of Britain will not take place, but we are a long way from being relieved of that threat."

Hitler to Attack Us

Assuming that Britain might fail, Leach attacked those who believe that Hitler would leave us alone. "If you were Hitler in June, 1941, would you let the United States go right on manufacturing guns, ships, tanks, and planes, the purpose of which could be only for use against you?"

Leach doubted whether, in the event of a British defeat, South America would be an asset to us. South America can be acquired "at blitzkrieg tempo" by a ruthless nation with a strong fleet and long-range bombers, he said, and our good-neighbor policy is "an artificial trifle" when compared with that threat.

Despite the diligent efforts of the FBI and Military and Naval Intelligence Departments, we know we will suffer from sabotage of great consequence "just as surely as we know the sun will rise tomorrow," he said. Saboteurs are not doing much damage now because there are not large enough accumulations of munitions to make it worth while.

Propaganda Not Dangerous

Foreign propaganda is not very dangerous compared with possible sabotage he said. If we adopt Hitler's point of view, moreover, it is obvious that Germany will not allow our defense efforts to continue unimpeded.

Leach condemed those who had faith in our embroyo defense program, our air force still on order, and "the gentleman from Cedar Rapids, Iowa, who calls himself a 'two-fisted isolationist'." Leach had interrogated Verne Marshall on the New England Town Meeting of the Air last week, when the latter remarked, "Boy, what a question-asker you are.