I was unaware of a Cold War between the two states, but today the Supreme Court allied with Delaware in its attempt to block New Jersey from building a liquified natural gas pier on the other side of the Delaware River. Turns out that the First State has jurisdiction over the entire river along Delaware’s northern boundary, right up to the spot where the pier would stick out from the Jersey shoreline. As the Wilmington News Journal‘s Jeff Montgomery explains:

Most river boundary lines run along the middle of a waterway, but a late 17th century deed made all of the Delaware River — from shoreline to shoreline — part of Delaware along the state’s northernmost 29 miles of waterfront.

The News Journal account also includes this ominous sentence:

Opponents of BP’s plan hailed the decision as a clear victory for Delaware and its Coastal Zone Act conservation law, while one New Jersey lawmaker warned that it could further sour cross-border relations.

I hope the dispute doesn’t escalate. These two states definitely have the capability for a lot of chemical weapons.