While the term "freedom" is often used interchangeably between the 2 kingdoms, they have different roles. There are many similarities and even trying to define religious freedom and Christian freedom is often difficult as many people use the terms interchangeably.
The main question that it comes down to is: do Christians living under persecution in their country still have freedom in Christ, even though they don't have religious freedom? Freedom in Christ is something that no government or outside source can touch, and that is the difference.
They also talk a bit about how we honor "heroes" whether military heroes, or Christian heroes. But as they attempt to define all of these terms, they wrestle through how both types of freedoms are both good--just different. It's when we start seeing them as the same when trouble starts.