The Taliban surged back to power two decades after U.S.-led forces toppled their regime in what led to the United States’ longest war.

Since 1992, negotiations have produced notable accords on climate change, including the Paris Agreement. But leaders have so far failed to slow global warming. Trace the successes and failures of UN climate conferences ahead of COP26.

Negotiations between the United States and North Korea have proceeded in fits and starts for decades. But they have failed to halt the advance of North Korea’s nuclear and missile programs.

Since India’s independence, ties with the United States have weathered Cold War–era distrust and estrangement over India’s nuclear program. Relations have warmed in recent years and cooperation has strengthened across a range of economic and political areas.

Disputes over overlapping exclusive economic zones in the South China Sea have intensified in recent decades, while the territorial row over the Senkaku/Diaoyu Islands in the East China Sea dates bac…