What makes a question in Spanish rhetorical?

Question

In German, the placement or usage of single words shifts the meaning of a rhetorical question, in English, additionally distinct marker phrases are common for this purpose.

Are there specific terms/phrases or grammatical structures that make a question including a statement rhetorical in Spanish?

For example, the statement and question is

Has the growth of the Roman Empire forced its own decline?

How would you formulate this question using Spanish terms/grammar to denote/imply to a non historian that the statement

• is true
• is wrong
• is uncertain, so you don't want to express any rhetorical meaning (I take this case also as not everyone picks up a question immediately as rhetorical, but as a real question)

I mean especially more subtle ways (single terms/grammar shifting the meaning completely, no use of subordinate clauses and direct addressing of the audience) as

We all know that the growth ... decline, aren't we?

Your questions should differ in as few terms/grammatical structures as possible, but still clearly shift the rhetorical meaning between the 3 cases, so I can see how this can be done in an eloquent and subtle way in Spanish.

Answer 1

Acaso is a useful word for this purpose.

Given this non-rhetorical translation:

¿Forzó el crecimiento del Imperio Romano su propia destrucción?

We could make it rhetorical and imply it's wrong:

¿Acaso forzó el crecimiento del Imperio Romano su propia destrucción?

Or right:

¿Acaso no forzó el crecimiento del Imperio Romano su propia destrucción?

Answer 2

An almost literal translation of your example rhetorical sentence as

Todos sabemos que el crecimiento del imperio romano forzó su propia destrucción, ¿o no?

However, it is unclear whether the doubt is placed on the knowledge of the fact or the truth of the fact.