This is a win-win situation for anyone.
Why? Unlike reality nations refuse or over look this aspect until they are at war with a formidable foe.
Just look our country, we have strong allies but look how our economics is tied and about to implode?
So how do someone here build a stronger alliances?
It is a matter of time and patience.

It also does not matter if they new or old, you should take the time to get to know your strengths and weaknesses of both your country and allies.

To make this short, take it slow when forming an alliance, then arrange meetings,etc... to discuss issues that interfere with your core goals and vision.