If sanctions were used only when their consequences were certain, then they would never be used at all; and uncertainty is no excuse for doing nothing, because that could be just as dangerous.

如果只在后果明确的情况下实施制裁，那么就不会有制裁发生了；不确定不是无所作为的借口，因为无所作为同样危险。

youdao

But if we show weakness now, if we allow the plea for more time to become just an excuse for prevarication until the moment for action passes, then it will not only be Saddam who is repeating history.

BBC: Blair speech - key quotes