  Diffraction fundamentally limits our ability to image and characterize
exoplanets. Current and planned coronagraphic searches for exoplanets are
making incredible strides but are fundamentally limited by the inner working
angle of a few lambda/D. Some crucial topics, such as demographics of
exoplanets within the first 50 Myr and the infrared characterization of
terrestrial planets, are beyond the reach of the single aperture angular
resolution for the foreseeable future. Interferometry offers some advantages in
exoplanet detection and characterization and we explore in this white paper
some of the potential scientific breakthroughs possible. We demonstrate here
that investments in 'exoplanet interferometry' could open up new possibilities
for speckle suppression through spatial coherence, a giant boost in astrometric
precision for determining exoplanet orbits, ability to take a census of young
giant exoplanets (clusters <50 Myr age), and an unrivaled potential for
infrared nulling from space to detect terrestrial planets and search for
atmospheric biomarkers. All signs point to an exciting future for exoplanets
and interferometers, albeit a promise that will take decades to fulfill.
