Alien Offensive - Book 4 - Virulent Virus. Alien Offensive, #4

In episodes one, two, and three, a distant alien species whose home planet was in danger because of a failing red dwarf star, tried to eradicate all life on Earth and then terraform the planet to meet their needs. Thanks to the exceptional talents of two inspired physicist, who devised two unique weapons, each tailored to repel the desperate and repeated alien assaults, the world was spared not once, but twice.
Humankind celebrated their victories and felt safe from future aggressions, but those celebrations were premature. A renegade alien Commander, now repelled for the second time, and against the orders of his Elders, contrived plans to return to Earth with a world-destroying weapon of his own - this time determined to succeed. The third assault was also rejected, and the aggressive alien flotilla returned home to rearm.
However, the President of the United States refused to wait for another attack. While uniting the world in an unprecedented harmony of mutual cooperation, the visionary President amassed an armada of futuristic space-going, destroyers, and using advanced wormhole technology, learned from a captured alien, sent the destroyers to atomize the aggressive alien's home planet. Now positive the Earth was safe from any future attacks, the President, in his last year in office, and using the radical new technology learned from the captured alien, proposed the construction of a deep space research vessel, actually, a space navigating city.
It was to serve as a research platform with the intent of finding other worlds on which humankind would leave footprints and possibly colonize. That was nearly ten years ago and the building of the deep space exploration vehicle, dubbed, Messenger Two, is nearing completion .