A country subject to rocket attacks from across its border has a right to defend itself, even if its own actions can be construed as having provoked the attacks, and the attacks themselves are relatively ineffective. But a right of self-defense does not mean a right to do anything that can be construed as a defensive act, regardless of the cost to civilians.
哈马斯打向以色列的火箭弹引来了军事反应。一个受到来自境外的火箭弹袭击的国家有权采取自卫，即使可以说是它自己的行为招致了火箭弹袭击，并且袭击相对来说毫无效果。但自卫权并不意味着任何可以解读为进攻的权利，不管其平民所遭到的打击。