Neutrality prevented either side from lawfully opening battle inside the harbor, whose territorial limit is treated here as the range of shore cannon. As Phoebe passed close to Essex, Hillyar saw anchors rigged from the yards for grappling and hauled away. One interpretation is that the close pass let him assess Porter's nerves and intentions. An alternative explanation, that he hoped to provoke the Americans into firing first, is rejected in favor of that reading. Porter's conspicuous preparations revealed his preference for a close boarding fight.
Notable Point · 1:16:49-1:21:28
Cannon range defined neutrality while Porter's anchors revealed his plan
Valparaiso's protected waters extended as far as its coastal guns, and Essex's visible grappling preparations showed Hillyar that Porter wanted a close boarding fight.