what would we do with "proper near earth detection" other than contemplate our impending doom? lowest estimate for lead time to prepare an interception mission

what would we do with "proper near earth detection" other than contemplate our impending doom? lowest estimate for lead time to prepare an interception mission is one year, and even still the probability of success is not clear. https://en.wikipedia.org/wiki/Asteroid_impact_avoidance https://en.wikipedia.org/wiki/Asteroid_impact_avoidance