This example visualizes national contiguity using a force-directed graph, where each country is represented by a flag sprite node and connections between bordering nations are shown as red links. It uses D3 v3’s `d3.layout.force` to simulate the physical layout, with nodes and links animated over time as the simulation runs. Hovering over a flag triggers a tooltip displaying the country name. The data is loaded asynchronously from a remote JSON file hosted on GitHub.