In my opinion, it's recommendable to secure sensitive internal sites with TLS.

The reasons:

• If an attacker has gained an initial low-privilege foothold on your network, they'd have a bigger attack surface (through packet sniffing and the like) to do privilege escalation if your admin pages weren't properly secured.
• It might be naive to exclude the possibility of malicious actors within the internal network.

In my opinion, it's recommendable to secure sensitive internal sites with TLS.

The reasons:

• If an attacker has gained an initial low-privilege foothold on your network, she'd have a bigger attack surface (through packet sniffing and the like) to do privilege escalation if your admin pages weren't properly secured.
• It might be naive to exclude the possibility of malicious actors within the internal network.

In my opinion it's recommendable to secure sensitive internal sites with TLS.
The reasons:
 

• If an attacker has gained an initial low-privilege foothold on your network, she'd have a bigger attack surface (through packet sniffing and the like) to do privilege escalation if your admin pages weren't properly secured.
   
• It might be naive to exclude the possibility of maleficent actors within the internal network.
   

In my opinion, it's recommendable to secure sensitive internal sites with TLS.

The reasons:

• If an attacker has gained an initial low-privilege foothold on your network, they'd have a bigger attack surface (through packet sniffing and the like) to do privilege escalation if your admin pages weren't properly secured.
• It might be naive to exclude the possibility of malicious actors within the internal network.