And that's our obligation to send them to war only when we have to, and only when we know they can actually achieve their mission is a key difference between what I advocate and what the neo-cons advocate.

我们有义务,在必须的时候，送他们上战场，我们必须确保,他们一旦奔赴战场就能完成使命,这是重大的不同,我和新型保守派主张的不同之处主要在此。

普林斯顿公开课 - 国际座谈会课程节选

So conceptually the key difference here, besides the syntax looking slightly different, it just means that if you want a chunk of code to execute no matter what initially, ; you can use the do while loop; if you want to check a condition first, you can use the while loop.

所以概念上，则关键的区别是，除了语法看起来有点不同，它的意思是如果你想要一段代码,最初无论如何都要执行，你就可以用do，while循环;,如果你想要先检查条件，你可以用while循环。

哈佛公开课 - 计算机科学课程节选