Perhaps if the issue was brought to the courts the Guardian may have become subject to a court order (let's say, a gag order), which even if violated in the US

Perhaps if the issue was brought to the courts the Guardian may have become subject to a court order (let's say, a gag order), which even if violated in the US could have lead the Guardian to be in contempt. I think in this case a small retreat was more effective than a direct confrontation.