What is the endgame with talk of taking over Greenland, Canada, Panama Canal? In reality, could he do it? For what purpose?

My fully vaxxed teen & other fully vaxxed kids at school got it. None got very sick but took while to dx while still infectious. Is the efficacy not as good in the more recent vax? Are older teens higher risk due to proximity with others and yrs since booster? Should we revisit how often to boost?