In pp scattering at LHC energies, large numbers of elementary scatterings will contribute signifi cantly, and the corresponding high multiplicity events will be of particular interest. Elementary scatterings are parton ladders, identified with color flux tubes. In high multiplicity events, many of these flux tubes are pro duced in the same space region, creating high energy densities. We argue that there is good reason to employ the successful procedure used for heavy ion collisions: matter is assumed to thermalize quickly, so that the energy from the flux tubes can be taken as initial condition for a hydrodynamic expansion. This scenario gets spectacular support from very recent results on Bose–Einstein correlations in pp scattering at 900 GeV at the LHC.