You can debate whether it was ethical to use them or not, but you can't say it was irrational. They were at war with the country and trying to use every advanta

You can debate whether it was ethical to use them or not, but you can't say it was irrational. They were at war with the country and trying to use every advantage to end it as quickly as possible. That's very different than starting a nuclear war for the hell of it knowing your country will be totally destroyed as a result.