The water-energy-food-carbon (WEFC) nexus in drylands faces governance challenges due to the lack of quantitative frameworks for resolving synergy-tradeoff conflicts among Sustainable Development Goals (SDGs). We expand the WEFC framework by integrating seven SDGs across socioeconomic, ecological, and resource dimensions, thereby overcoming single-dimension limitations. Socioeconomic-environmental feedbacks are incorporated into the nexus. Impulse response analysis is employed to capture dynamic SDG interactions, moving beyond the static paradigm of conventional coupling coordination studies. By conceptualizing the nexus as a dynamic interconnection among seven SDGs, we develop a WEFC assessment index towards SDGs (WEFC-SDGI) to address inconsistencies in SDG evaluation. From 2000-2023, WEFC-SDGI in global drylands increased significantly at an annual rate of 1.95 (p < 0.05). However, only 37.1% of countries are projected to achieve the 2030 targets. The synergy and trade-off network highlights adaptive water-centric policies as pivotal, generating cascading benefits for energy security, food systems, and climate resilience. Our framework proposes diversified development pathways for global drylands to reconcile resource scarcity with accelerated SDG implementation and support progress toward the 2030 Agenda.