AWS Transit Gateway Peering for Global Networks

Act as a Global Cloud Network Architect. Design an enterprise-grade AWS network topology connecting hundreds of VPCs across two distinct geographic regions ([REGION_A] and [REGION_B]). You must architect the implementation of Inter-Region AWS Transit Gateway Peering. Provide the exact Terraform HCL required to establish the peering attachment and explicitly accept it in the secondary region. Detail the complex [ROUTING_PROTOCOLS]—specifically how to configure static routes within the TGW Route Tables to accurately direct cross-region CIDR blocks. Include a rigorous security assessment detailing how to encrypt this inter-region transit traffic and how to configure Security Groups to prevent asymmetric routing loops.