Unraveling the Proton's High-$x$ Structure with the EIC*

The problem of disentangling the $x$ and flavor dependence of the nucleon's valence-region parton distribution functions (PDFs) has received great attention in recent years, owing especially to the ongoing JLab 12 GeV program as well as activities at the LHC and elsewhere. This effort will only accelerate in the coming years in anticipation of the eventual science program of the Electron-Ion Collider (EIC), which will possess extensive resolving power in the high-$x$ region. In this talk, I will review our present understanding of the nucleon's unpolarized PDFs at high $x$ with a focus on the phenomenological implications thereof. Going forward, I will highlight the prospect for the EIC to drastically clarify our picture of the nucleon at high $x$ in the context of its broader program in hadronic tomography and precision QCD.