Why were the Romulans so blase about the Dominion after it gained a foothold in the Alpha Quadrant?

Question

Early on in season three the Romulans seemed to consider the Dominion a threat even though they were still on the other side of the wormhole, as shown by their actions in the following episodes:

• The Search, Part 1: loaning Starfleet a cloaking device (despite a certain clause in the treaty of Algernon) in exchange for intelligence gained about this newly discovered power,

• Visionary: sending a warbird to destroy DS9 so it couldn't stop them from sealing the wormhole entrance

• Improbable Cause & The Die is Cast: building a joint fleet with the Cardassians for the purpose of a sneak attack against the Dominion's rulers (this was the Tal'Shiar, the actual military was not party to this, but still).

However in season 5's A Call to Arms and most of season 6 the Dominion has come through the wormhole, gained control of the Cardassian Union, and is effectively winning against both the Federation and the Klingons (up until Sacrifice of Angels, anyway); yet the Romulans seem to have this naive "Oh they'll stop once they conquer those guys" attitude. It took the events of In the Pale Moonlight to get them involved and that was based on a deception by Sisko and Garak.

What I'm asking is: why did the Romulan Star Empire treat the Dominion more like a threat before it came nearer their side of the galaxy than they did after?

Answer 1

The Romulans enjoyed their Alpha Quadrant brethrens' plight and were happy to be part of a winning alliance rather than wage a possibly hopeless war.

At first, it was the shared belief of the Alpha Quadrant powers — Romulans included — that the Dominion could be reasoned with or, if necessary, defeated. But it became increasingly clear that both outcomes might be impossible, given the resolve of the Founders and the stunning defeat of the Romulan / Cardassian surprise attack on the Founders' home world.

This would certainly lead to a shift in Romulan policy, towards using the Dominion to defeat the enemies of Romulus instead of trying to wage a possibly hopeless war against the Dominion.

Indeed, the Romulans have always enjoyed seeing the Federation and Klingons suffer, by pitting them against each other or finding other ways to weaken them. The Romulans demonstrate this in Enterprise, Star Trek VI: The Undiscovered Country (the Romulans conspired to keep the Federation and Klingons at war), and in TNG (where they fuelled the Klingon Civil War and tensions with the Federation). Watching the Dominion dismantle the Federation and the Klingon Empire would be ultimately very satisfying to the Romulans.

Finally, in the episode "In the Pale Moonlight", Senator Vreenak explains the position of the Romulan Star Empire to Sisko:

VREENAK: You are persistent, Captain, I'll grant you that, but dogged determination isn't enough to change the reality of your situation. Time is definitely not on your side. The Dominion shipyards are working at one hundred percent capacity. Yours are still being rebuilt. The Dominion is breeding legions of Jem'Hadar soldiers every day. You're experiencing a manpower shortage. But most important, the Dominion is resolved to win the war at any cost. You and I both know the Federation has already put out peace feelers. Now, in all candor, if you were in my position, which side would you choose?

In the same episode, Dax makes a similar analysis:

DAX: Think about it. They're in the perfect position. They get to sit back and watch as their biggest rivals slug it out in a long, bloody war. No one's threatening their interests. Why should they risk their necks? There's simply no reason for them to get involved in our war. No reason at all.