have a foot in both camps

The Japan TimesのLIFE欄に白洲正子さんに関するエッセイがありました。have a foot in both campsはもともと軍事表現で「敵味方双方に通じる」という意味があり，そこから転じて「二またをかけている」という意味があります（『プログレッシブ英和中辞典』小学館）。今回は戦後間もないという時代背景を意識しているとも考えられますが，ここでは「（日本とアメリカの）２つの文化的な価値観を持っていた」と解釈してみました。（Koyamamoto）

Masako Shirasu: woman of the world
Essayist Masako Shirasu helped define the tastes of postwar Japan in almost every aspect of aesthetics and design
“If you use beautiful things every day, you will naturally cultivate an eye for beautiful things without giving it a second thought. In the end, you will be repelled when you encounter the ugly and the fake. If only all Japan would come to see this, how much more joyous our lives would be and how genial and gentle people would be!”
... Masako had a foot in both camps from a very early age. At the age of 4, she began taking lessons in noh theater, the ritualistic performance art that had come to be the symbol of staid refinement during the Edo Period (1603-1867). When she was 14, she became the first female to perform on a noh stage. At the same age, she left Japan to enter school in the United States.
http://www.japantimes.co.jp/life/2014/03/01/lifestyle/masako-shirasu-woman-of-the-world/#.UxMbkRzV1Pw