GPAs barrels

The video discusses areas in the US controlled by an ASF service command and the subsequent events that unfold. It highlights the delayed impact of these events, which are felt thousands of miles away, from Omaha and Dallas to the Gulf. The narrative describes a mighty army moving quietly and secretly, deploying its weapons.

What does the phrase 'Felt only later' imply about the impact of the events?

What can be inferred about the military presence from Omaha to the Gulf?