How did David intend that Uriyah will die?
Malbim: Normally, in war there is a zone of fierce fighting where Giborim risk their lives. Uriyah will be among them. The others will retreat and not save him. This will cause his death; he was Chayav Misah (refer to 11:9:1:1 and the note there 1 ). David did not endanger anyone else in order to kill Uriyah.
Malbim: Why did he not execute him via Sanhedrin, for Mored b'Malchus? He needed to cover up the matter, to avoid complaints and rebellion; He knew that he must marry Bas Sheva (to cover up that she became pregnant from David before Uriyah died - Malbim (verse 26). R. Tzadok ha'Kohen (Poked Ikrim 5) - David knew via Ru'ach ha'Kodesh that Bas Sheva is destined for him, and Mashi'ach will come from her.) (Also, if the Get was on condition that he dies in the war, perhaps execution is not included, so David would remain with the Aveirah of Eshes Ish. However, David could have told him, you are Chayav Misah. If you prefer, you may fight against Amon by yourself! - PF)
Why did David want Uriyah to die in the war?
Rashi: Then his wife will be divorced retroactively, for soldiers used to give a Get 'on condition that I die in the war.'
