Exactly. One of the base assumptions of the Fermi paradox is that travel between solar systems is practical, which is far from proven at this point. If we are

Exactly. One of the base assumptions of the Fermi paradox is that travel between solar systems is practical, which is far from proven at this point. If we are bound by the rocket equation, that is to say if Newton's First Law holds, then the answer to the Fermi paradox is simple. Travel between solar systems is less practical than just colonizing your own solar system, even through extreme measures like swarms of orbital colonies. When you think about it, an interstellar starship that must expend mass to change velocity is going to have to make a severe tradeoff between mass and travel time. In practical terms you have to first build a colony that can sustain itself indefinitely in your own solar system before you build one that can also accelerate/decelerate to a million kph and doesn't have the advantage of being near a free source of energy or any sources of new materials.