In fact, they are negative because they say that this can't be done without opening up the service to vulnerabilities that could be used by others.
> I ett brev till regeringen skriver Försvarsmakten att lagförslaget inte kommer kunna förverkligas ”utan att införa sårbarheter och bakdörrar som kan komma att nyttjas av tredje part”.
> In a letter to the government, the Swedish Armed Forces writes that the legislative proposal will not be able to be implemented "without introducing vulnerabilities and backdoors that may be utilized by third parties."
Yes, but your deduction is incorrect. They're saying the SAF are negative _and_ they recommend their personell to use the service, not that they are negative _because_ they recommend it.
I don't see how you can know that "because" is incorrect. This seems like it could be possible to me:
(Possibly) SAF is negative because they use Signal, and don't want a law that would introduce vulnerabilities into Signal that could be utilized by third parties.
> I ett brev till regeringen skriver Försvarsmakten att lagförslaget inte kommer kunna förverkligas ”utan att införa sårbarheter och bakdörrar som kan komma att nyttjas av tredje part”.
> In a letter to the government, the Swedish Armed Forces writes that the legislative proposal will not be able to be implemented "without introducing vulnerabilities and backdoors that may be utilized by third parties."