Really? I always considered D'Hara to be the least isolated realm in the continent. It is probably the one who borders more realms, and it is in the middle of everything, connecting everyone.
In the middle of everyone, yet has been neutral in all wars raging around them since years and years and years. Last time people tried to invade us, that didn't turn out too well for them.
We are in the "middle", but damn far from everyone still. When I held a tournament and put the maximum delay, hardly anyone on the continent could make it on time.
In the same sense, many people have links to D'Hara within but a few regions to cross, but the travel times are pretty darn long. And they all lead to pretty high walls with easy recruiting capacity. Before the addition of delayed arrival, it was pretty much impossible for invading armies to arrive in a coherent manner. As such, we never had to bother recruiting much troops, because we could take one much larger forces than ourselves just thanks to that. And because of how hard we are to crack, people have not acted on aggressive words since Madina.
We are next to everyone, and never had to submit to any bloc. We've made our own bloc with other pretty isolated realms (but not from us), but never had to participate in any of the big events on the continent, despite our ability to. That's thanks to the potential for isolationism, to live on doing our own thing regardless of the chaos that rages around us.