こそ

こそ is a strong emphasis particle used to single out and highlight the word or phrase it attaches to. It marks the element as especially true, important, or surprising, often contrasting with other possibilities or expectations. It can create a sense of exclusivity: Xこそ is the thing you want to emphasize as the real thing, the one that matters, or the one that is true in contrast to others. It is common in assertions, resolutions, or rhetorical statements, and it frequently shifts the nuance from a general statement to a pinpointed assertion.