I disagree with the excerpted use of Resolved.
Here is a quote from an online version Robert's Rules.
If it is desired to give the reasons for the resolution, they are
usually stated in a preamble, each clause of which constitutes a
paragraph beginning with "Whereas."
Whereas, We consider that suitable recreation is a necessary part of a rational educational system; and
Whereas, There is no public ground in this village where our school children can play; therefore
Resolved, That it is the sense of this meeting that ample play grounds should be immediately provided for our school children.
Resolved, That a committee of five be appointed by the chair to present these resolutions to the village authorities and to urge upon them prompt action in the matter.
In the examples you cite in the second paragraph, I would only agree with the third Resolved. The others should use Whereas.
In "The United States is losing the War on Terror," the deliberative body is not deciding (or Resolving) to do anything. It is a preamble to a resolution. Same for "The costs of legalized casino gambling in the U.S. outweigh the benefits." These both need a Whereas followed by a later "Resolved" and a resolution.
The excerpt provides the decision in "Resolved: The United States should issue guest worker visas to illegal aliens." This is the correct usage.
- Whereas, The usage of whereas and resolved were established by Brig. Gen. Roberts in 1876, and
- Whereas, Some modern usage of whereas has been confused with resolved; therefore
- Resolved, That questions be posted to a suitable online forum to inquire as to correct usage of resolved.
- Resolved, That authors, legislators, and members of deliberative bodies observe and employ the correct usage of whereas and resolved.