What sort of judgment does the Captain make about the place they are fighting for? How does Hamlet describe it?

In act 4, scene 4, Hamlet is on his way to England. He sees the Norwegian king, Fortinbras, lead his army through Denmark, and is curious to know where they are going. He questions one of the king's captains, who tells him that the Norwegian troops are off to invade Poland. The captain isn't very flattering about the land the Norwegians are planning to invade:

Truly to speak, and with no addition, We go to gain a little patch of ground That hath in it no profit but the name. To pay five ducats, five, I would not farm it. Nor will it yield to Norway or the Pole A ranker rate, should it be sold in fee.

In other words, it's just a small piece of territory, with very little strategic or economic value. It's neither use nor ornament to anyone, Norwegians or Poles. The whole military expedition to seize it is pretty much a waste of time.
The captain's remarks cause Hamlet to muse on the utter futility of Fortinbras's forthcoming military campaign:

Two thousand souls and twenty thousand ducats Will not debate the question of this straw. This is th' impostume of much wealth and peace, That inward breaks and shows no cause without Why the man dies.

Hamlet is even more scathing than the captain about the wisdom of the expedition. He's absolutely certain that, even with such a large invasion force ("Two thousand souls"), even with all that money ("Twenty thousand ducats"), there'll be no speedy resolution to this conflict for the Norwegians.