Fury's responce was nearly verbatum what was to be expected. Jack may have had a brief expression of surprise on his face, but in all honesty, that was just because he had half expected Fury to fire a round in his general direction to drive home the point.
If you looked in the dictionary, under the word Unflappable, you'd see a picture of Nick Fury.
"So...what happens if the portal closes? Does it always reopen in the same place, or do we have to go looking for it?"