We've gotten to the bridge, and now it's time to take a decision about crossing it. Daenerys Targaryen has reached out to the King in the North, Jon Snow, has granted him and audience and asked him to 'bend the knee' in front of her. After receiving Samwell Tarley's scroll from the Citadel about the large deposits of dragonglass under Dragonstone, Snow is equally keen to meet the mother of the dragons. After all, Jon Snow knows it all too well that winter is upon the seven kingdoms and the only way to survive it would be alongside trustworthy allies and a righteous ruler.
Let's speculate the merits and the demerits of this alliance, and what chances it would stand in the Great War:
1. The vast reserves of Dragonglass in Dragonstone.
The single most important thing for any army to stand a chance against the army of the dead. And now that Jon knows about the reserves in Dragonstone, one can be rest assured he will try to make the alliance work. Since, Jon is the only one to have survived an attack from the white-walkers. However, Daenerys insists that the King of the North 'bend his knee' in front of her, and it will be interesting to see if the pride gets in the way.
2. Jon Snow's strong foot-hold in the North.
Jon Snow currently commands all the houses of the North, the wildlings and the wall of the North, which is the only thing standing between the white-walkers and Winterfell and the rest of the Westeros. Daenerys will need Jon Snow's help against fighting the army of the dead, if she has to rule the seven kingdoms. And for a peaceful North, she will need Jon Snow or a Stark as the Warden of Winterfell.
3. After losing the Greyjoys and Dorne, Daenerys will need Winterfell as an ally more than ever.
Currently, Daenerys has the Tyrells, the army of the Unsullied and the dragons at her disposal. And after Euron's attack which resulted in the capture of Yara Greyjoy and Ellaria Sands, she has lost two allies and she needs allies in the form of Winterfell more than ever.
4. Cersei, Euron and the unpredictable Qyburn might not be the pushovers we might think.
Cersei and Jaime are struggling to find allies, now that House Tyrell has openly pledged their allegiance to Daenerys Targaryen. House Tarly might be one of the crucial allies for the Lannisters, who in spite of their allegiance to the Tyrells, might choose the Iron Throne over an outsider. Also, as Episode 2 suggests the evil, unpredictable maester Qyburn (who orchestrated the explosive finale of season 6) might have developed a remedy to take of the dragons of Daenerys Targaryen.
5. The battle of Casterly Rock will be an important factor in how the Great War pans out for the Lannisters.
Greyworm and his army of the Unsullied are on their way to hit the Lannisters where it hurts most - their home. As both Cersei and Jaime work day and night to keep themselves on the Iron throne, they might have overlooked the defences of their home. If Daenerys captures Casterly Rock, it will be a huge setback for the Lannisters and their claim as the ruler of the seven kingdoms.
6. The interesting dynamic between Sansa and Daenerys IF this alliance takes place.
If this alliance works out, Jon Snow being the devoted idealist that he is, will serve Daenerys with all his might. But Sansa Stark has come a long way, and been a toy for too many powerful people to fully invest her faith into Daenerys. And being perceptive as she is, will Daenerys be able to watch her back for Sansa? We'll have to wait and watch.
Compared to the earlier seasons, this one's making fast progress and all episodes here on promise to be action-packed. And if this alliance takes place as has been hinted in the trailer of Ep 03, they will have a strong claim to the throne. But as we all know George R R Martin always has a surprise up his sleeve? It looks to easy for this alliance, and that's where we might be wrong.