Is the presence of American military forces in Japan like the Russian military forces in your country?
If the Russians withdrew their troops from your country, would that diminish your self-defence capabilities?
この場合、次のような言い方ができますよ。
ーIs the presence of American military forces in Japan like the Russian military forces in your country?
「日本でのアメリカ軍の駐留は、あなたの国のロシアン軍の駐留と同じですか？」
presence で「（軍隊の）駐留」
ーIf the Russians withdrew their troops from your country, would that diminish your self-defence capabilities?
「あなたの国からロシア軍が撤退したら、あなたの国の自衛力は弱まりますか？」self-defence capabilities で「自衛力」
ご参考まで！
カナダ 
