The Vesta Blockade was a confrontation between the United Nations and Martian Congressional Republic centered on the asteroid Vesta. Not much direct information is known about the event, with the event only mentioned in dialogue.
The causes of the Vesta Blockade are unknown, though it involved a UN blockade of the asteroid Vesta, with an embargo placed on Martian terraforming supplies. The Vesta Blockade involved five UNN destroyers, including the UNN Yasijuro, facing off against one MCRN cruiser, with a twitch reaction escalating the situation into a shooting battle. Although a ceasefire was ordered within minutes, the lone MCRN cruiser was able to cripple all five UN destroyers single handedly. During the battle, the future-admiral Augusto Nguyễn saw twenty-nine personnel on the Yasijuro blown into space due to decompression. During the crisis, half of the UNN fleet was on a hard burn to Mars to destroy its former colony, though cooler heads eventually prevailed.
The effects of the blockade caused the MCRN to begin a serious campaign of militarization in an effort to keep their military power on par - if not better than - their Earth counterparts, in the process delaying its terraforming project by a century, ensuring that no one alive at the time would live to see an ocean on Mars.