can do nothing but; only ~
Expresses that there is no option other than the stated action or state; 'can do nothing but' or 'only'.
This is a formal, literary pattern used in written Japanese, speeches, or dramatic narration. It emphasizes that the situation leaves no other choice or that something is the sole remaining thing. For verbs, it means 'all one can do is ~' or 'only ~'. For nouns, it means 'only ~' or 'nothing but ~'. The ただ at the beginning adds a sense of 'merely' or 'nothing else but', and のみ is a formal equivalent of だけ. The ending だ can be replaced by です in polite speech, but the overall tone remains stiff and bookish. In conversation, you'd typically use だけ or しかない, but this pattern is used in essays, news, and formal statements.