The last 20 years has seen an explosion in the number of known planets beyond our Solar System. Recently, this has included the discovery of a handful of potentially habitable worlds. However, to test their habitability, and search these planets for signs of inhabitance, we require a mission that is designed - from the ground up - with exoplanet characterization in mind. That characterization will take place via anaylsis of spectra from exoplanets, which will yield inferences on the composition of and mass fluxes from the planet’s surface. Such a mission would face three sets of challenges in technology, community dynamics, and science. In this presentation, we will discuss how future space-based telescopes can overcome the technical challenges, how NASA’s Nexus for Exoplanet Systems Science is addressing the community dynamics challenges, and how we can leverage the resulting community to address the science questions.