Let them be confounded - Let them be ashamed. That is, Let them have that kind of shame and confusion which results from the fact that their plans have not been successful, or that they have been foiled and baffled in their schemes.
And troubled - Disturbed; put to confusion. Let them be troubled as men are who are unsuccessful in their projects.
Forever - As a people; as confederated nations; as united in such an unholy alliance. Let them never again be able thus to combine, or to form a compact for the destruction of thy people. This does not refer to them as individuals, but as nations. It is a prayer that they may be so discomfited now that they may see the wickedness and folly of all such efforts, and that they may never again form such a combination.
Yea, let them be put to shame - By utter failure in their schemes.
And perish - Not individually, but as combined - as an alliance. Let there be a complete end to such a confederacy, so that it shall never be seen again.