It's not like Palantir is selling hamburgers to millions of faceless individuals. They themselves want to take the responsibility for their consulting for government agencies. I assign responsibility to them, too.
Can you think of examples of amoral company decisions from history? I can...
"Our bank just facilitated the deposit of enormous quantities of paper money. We didn't do the drug-smuggling."
"Our company simply supplied The Republic of ___ with ammunition. That was our only involvement."
"The government needed to sort incoming prisoners by religion. We merely won the bid to do the data-processing."
Palantir's arguments are more annoying, though, since the company management is not just amoral, but proud of itself.