George McGovern and his supporters committed what, in a two-party system, are capital crimes: they did not compromise, they took hard ideological positions, they alienated a large portion of their party's traditional supporters, and they lost - very, very badly.
While we use American power to fight hard for democracy against extremism on both left and right, our critics seem suspicious of any assertion of United States power or influence against any government or group that claims to be on the left.
In the Philippines, Gloria Arroyo is the daughter of Diosdado Macapagal - but his term ended in 1965, and she was elected in 2001. Hardly a hand-off.