The hierarchical structure formation is the cornerstone of modern cosmology. Galaxy clusters are assembled via the accretion and mergers of galaxies and groups. Deep Chandra and XMM-Newton observations of nearby clusters combined with specifically-tailored hydrodynamic simulations have provided us with qualitative constraints on the cluster merger history and the transport coefficients in the intracluster medium. I will discuss how future missions could allow us to measure gas motion and turbulence directly, revolutionizing our knowledge of the gas dynamics in the ICM and connecting the micro and macro scale astrophysics in galaxy clusters.