1)
How would they destroy Yisrael from being a nation?
1.
Radak: The remnant would be few and scattered when they flee.
2)
Why do they want that "Yisrael" will not be mentioned?
1.
Rashi (6): Since Yisrael will not be mentioned, also Your great name will not be mentioned. (You are called Elokei Yisrael.)
2.
Radak: They will cease to be a nation.
3.
Malbim: The name Yisrael shows that they are conducted above nature, and Hashem's Hashgachah is on them. They want to nullify Emunah and knowledge of Your Elokus in the world, which is via Yisrael.