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Here we show that precise Gaia EDR3 proper motions have provided robustestimates of 3D velocities, angular momentum and total energy for 40 Milky Waydwarfs. The results are statistically robust and are independent of the MilkyWay mass profile. Dwarfs do not behave like long-lived satellites of the MilkyWay because of their excessively large velocities, angular momenta, and totalenergies. Comparing them to other MW halo population, we find that many are atfirst passage, $\le$ 2 Gyr ago, i.e., more recently than the passage ofSagittarius, $\sim$ 4-5 Gyr ago. We suggest that this is in agreement with thestellar populations of all dwarfs, for which we find that a small fraction ofyoung stars cannot be excluded. We also find that dwarf radial velocitiescontribute too little to their kinetic energy when compared to satellitesystems with motions only regulated by gravity, and some other mechanism mustbe at work such as ram pressure. The latter may have preferentially reducedradial velocities when dwarf progenitors entered the halo until they lost theirgas. It could also explain why most dwarfs lie near their pericenter. We alsodiscover a novel large scale structure perpendicular to the Milky Way disk,which is made by 20% of dwarfs orbiting or counter orbiting with theSagittarius dwarf.

Gaia EDR3 proper motions of Milky Way dwarfs. II: Velocities, Total Energy and Angular Momentum