The Islamic State Khorasan (ISIS-K), a regional subsidiary of ISIS, is undergoing an ominous resurgence in Afghanistan, a country where U.S. military capabilities to monitor and counter such threats have drastically diminished. Retired Gen. Frank McKenzie, a former U.S. Central Command leader, expressed concerns over the diminished U.S. strike ability in the region, stressing that ISIS-K's threat to U.S. homeland security has escalated since American military withdrawal.

These threat assessments find echo in the recent ISIS-K orchestrated attacks in Iran and Russia, which have gruesomely reminded the international community of the terrorist organization's lethal capabilities and intent to orchestrate attack abroad. Notably, both Tehran and Moscow received prior intelligence warnings about potential assaults, hints that were missed or unheeded as per the information shared before the devastating attacks.

The major attacks included a bombing in Iran and a mass shooting in Russia that mercilessly claimed lives and exacerbated security concerns. The intelligence exchange and warnings, although significant, lacked precise information that may have hindered effective preemptive actions. U.S. officials, notably Maj. Gen. Patrick Ryder from the Department of Defense, assure that ISIS remains under surveillance despite the U.S.'s compromised physical presence in areas formerly under tight oversight.

This resurgence rekindles the memory of ISIS's rapid expansion following the U.S. withdrawal from Iraq, thereby inciting debates about the repercussions of military disengagements and drawing parallels with the current situation in Afghanistan post-U.S. forces departure. These developments incite scrutiny of intelligence-sharing efficacy and bilateral security responsibilities in preventing terrorism at an international level.

The alarming upsurge of ISIS-K activities in Afghanistan is a reflection of broader regional instability. Since the withdrawal of American troops from the region, Afghanistan has witnessed a significant power vacuum that terror groups like ISIS-K are trying to exploit. Despite the Taliban's retaliation against ISKP elements, there is a growing concern about the faction's potential to plot against both regional and international targets. The international community's focus remains riveted on the evolving dynamics in Afghanistan, especially the ability of the Taliban to contain the spread of such extremists.

General McKenzie's statements underscore a fear that runs deep through the ranks of international security agencies: the potential for Afghanistan to revert to a pre-9/11 state of terror haven. The U.S. drone program, once an effective tool for America's counter-terrorism strategy, now operates with diminished scope and frequency, raising questions about the efficacy of remote surveillance and strike programs in managing the ISIS-K threat from afar. Such decreased capability leads to the reliance on human intelligence and regional partnerships that are less effective and immediate than direct military action.

Analysts point out that ISIS-K has been carrying out sophisticated recruitment drives and leveraging the upheaval in Afghanistan to bolster their ranks with disillusioned fighters from various factions, including the Taliban. The ideological appeal of ISIS-K remains potent, particularly among the young and disenfranchised populations in Afghanistan and surrounding regions, which leads to persistent and unpredictable threats of terror activity.

The twin attacks in Iran and Russia, although disparate, signal a coordinated effort by ISIS-K to destabilize regional security and sustain their relevance on the international stage of jihadism. The brazenness of the attacks raises alarms over ISIS-K's operational reach and sophistication, and reinforces the notion that intelligence cooperation is crucial, but often flawed in practical application. The missed signals ahead of the attacks in Iran and Russia expose vulnerabilities which terrorists have exploited and will likely continue to attempt to exploit.

Maj. Gen. Patrick Ryder's assurances of continued surveillance efforts highlight an uncomfortable truth – although the United States retains the technological prowess to keep tabs on groups like ISIS-K, the lack of physical presence hampers on-the-ground reaction speed and comprehensive intelligence gathering. This can contribute to a less informed strategy for preemption and response, inevitably hindering efforts to dismantle or disrupt terror plots effectively.

Delving into the implications of U.S. military disengagement, security experts express concerns over a pattern that seems to facilitate a power vacuum and resultant surge in militant group activities. The parallels with the aftermath of the U.S. withdrawal from Iraq cannot be ignored. In both historical scenarios, the void left by U.S. forces was quickly filled by extremist groups, which in turn posed new threats to regional and global security. The resurgence in Afghanistan also reignites discussions on whether swift military withdrawals serve the long-term interests of peace and security stability.

The aftermath of the attacks in Iran and Russia brings to the fore the need for an integrated international response to the threat posed by groups like ISIS-K. The efficacy of intelligence-sharing networks and the political will to act upon them are paramount in this regard. Countries around the globe are called to prioritize intelligence collaboration and synchronize counter-terrorism measures to preempt the sort of attacks that ISIS-K has shown itself capable of orchestrating.

In conclusion, ISIS-K's resurgence is a complicated issue that intertwines the responsibility of governments to protect their citizens, the efficiency of international intelligence apparatuses, and the broader consequences of military withdrawals from conflict zones. It is a stark reminder of the relentless nature of global terrorism and the unyielding efforts required to counter it. Vigilance, collaboration, and adaptability will be the key elements in thwarting the ambitions of ISIS-K and securing the safety of nations worldwide.