Jonah was just selected as the official leader of the human civilization. At this point of time humans had made a lot of progress in technology and they were kind of thriving. But the betrayal in the organization was still a problem as an intergalactic war had already begun.
Human civilization was a main target as they were in the sweet spot of the galaxy where resources were enough for all purposes that includes sustaining an species and the most important part, energy for war. Jonah knew this well.
Jonah knew fighting the other species head on was a suicide as a lot of them could wipe the humans in an instant. So he decided to take out the weaker civilizations to conquer form which he could obtain more resources to fight.
Jonah is a strategic mastermind. He is very self dependent and relies on others very less. One thing about him was he is quite overconfident which gets him in a situation he doesn't desire but he has the ability to bounce back quickly.
"Bring me the cartographer." said Jonah in a demanding voice. The cartographer arrived. "Why have i been summoned?" asked the cartographer as Jonah sipping coffee said "I want you to make a map where i could start my conquest." The cartographer agreed.
After some time a map was done made. It appears the first one on the way is the 231B5 star system which holds a civilization which is known to exterminate the attackers before they could even get any closer.
About a distance of 220 light year which was extremely far. With the current technology it would take about 1490 years to complete the travel. But nothing should be done in a rush as the distance is very vast and tides could turn very quickly in such battle.