When push comes to shove means if the situation deteriorates or becomes desperate, and in this context the colonial union is making decisions based on that possibility.
Consider the statement "The colonial union is already making decisions about what colonies it can afford to lose if the situation turns for the worse and desperate measures are needed.". Based on this "The colonial union is already making decisions about what colonies it can afford to lose when push comes to shove." a true statement? Yes, no, or I don't know?