What is the meaning of "Hat Shamecha"?
Radak: This is like "va'Yet Shamayim va'Yered" (Bereishis 18:10). It is a metaphor, as if Hashem descended to eradicate Resha'im quickly. This Tefilah refers to kings of nations that wanted to fight with David.
Malbim: If You descend to destroy him 1 Yourself, all will see Your ability.
Surely he refers to a Rasha. (PF)
What are the "Harim"?
Radak: They are kings as strong as mountains; this is a metaphor.
Why does it say 'v'Ye'eshanu"?
Radak: When You send the fire of Your anger on them, smoke will come from them, like it comes from something consumed in fire. Many see the smoke, but do not see the fire. So in eradicating Resha'im - one who does not see their eradication will hear and know [of it].
Malbim: If You will not descend [to the ground, to destroy the Rasha Yourself], at least descend to the mountain tops, and they will smoke.
