New Delhi, May 28 -- Even as US Secretary of State Marco Rubio's India visit put the spotlight on bilateral ties, a four-way meeting of the top diplomats of Quad members-the US, India, Australia and Japan-that he attended in New Delhi on Tuesday has drawn attention back to the group's goal of a free and open Indo-Pacific.

The contextual irony is the unfree and closed Strait of Hormuz, which is near India's corner of the Quad's focal zone. Since America bears significant responsibility for this state of affairs, it's unlikely to have been a matter of much discussion.

The latest gathering, however, yielded key agreements on critical minerals, maritime initiatives and energy security. The subtext is an effort to keep an assertive China fro...