A retarded post
One of the main points of this weeks parsha talks about the commandment to conquer the land of Israel
First, this week's parasha also talks about the commandment to relinquish your rights for the sake of a higher purpose. Moreover, you can find anything you like in the parsha. Neat, huh?
Yehoshua understood this and made the people promise to conquer their desire to show mercy to the nations of Canaan, since doing so would only be to the detriment of the Am, as is clearly seen from not only ensuing generations, but our own as well.
Second, Moshe was commanded by God to fight Sichon (in last week's parsha no less) yet he explicitly violated the command and instead "pursued peace" by sending messangers to Sichon. I guess its true, that "lo kam b'yisroel k'moshe od," also to the detriment of the Am, etc.
As the Gemara says, he who is merciful to the merciless, will in the end be merciless to the merciful.
Third, who says we should be "merciful to the merciless?" No one.
I think, Litvish Yid, that you're confusing the immoral idea of being "merciful to the merciless" with the very moral idea of being "merciful to those who simply have an ethnic resemblance to the merciless."
As you prepare the pitchforks and torches, I hope you remember the difference.