"The convoy is on the grounds now and inside the defense perimeter," she said.

"You're inside the defense perimeter," the kid who'd waved said in careful English.

"Well, I set up a defense perimeter, sir," the officer continued.

A last defense perimeter, within which they must intend to fall back.

And order them to land outside the defense perimeter.

The first thing to do was to establish some sort of defense perimeter.

The barren defense perimeter must be just the other side.

"I set up a complete defense perimeter around this room," Elizabeth said.

Finding themselves outside the West's new defense perimeter, they would look to Moscow to meet their security needs.

Nearly all their ships are on the defense perimeter.