Just months after we ended our 20-year deployment to Afghanistan, New Zealand is redeploying troops - a mercy mission to bring home Kiwis and resettle Afghan nationals who worked for our Government.

Hundreds of Afghans and their families could be resettled in New Zealand, and our elite SAS troops could be tasked with keeping the operation safe. 

It will be ten years on Thursday since SAS Corporal Dougie Grant died helping save lives in Kabul - one of our 10 fallen soldiers in Afghanistan.

Watching what his brother fought to rebuild fall, Stuart Grant told Newshub it doesn't mean it wasn't worthwhile.

"I think you have to help where you can and when you can," he says. "I think that's what my brother did."

And that means continuing to help those who helped his brother and the rest of our troops.

"If there's any danger or any risk that we created as a country, then we should be doing what we can to help those people that were maybe put in that position because they helped us." 

Prime Minister Jacinda Ardern knows it - she's mounting a rescue mission, redeploying Kiwi troops to Afghanistan. 

"We have made a decision to deploy the C130 and accompanying personnel to support the international efforts to evacuate," Ardern said on Monday, adding that about 40 troops are being sent over. 

Air Marshal Kevin Short, Chief of the Defence Force of New Zealand, said it could be a month's deployment. 

"At this stage we're planning to deploy for a month but we don't know whether the security situation will allow us to operate for that long."

The situation is volatile and deteriorating quickly. 

READ MORE

• Our responsibility to support those who supported us: Jacinda Ardern plans to evacuate Afghan nationals and Kiwis amid Taliban takeover
• Kiwi journalist reveals what it's like to live in Kabul as Taliban takes control
• Utterly surreal and devastating': Former PM Helen Clark shellshocked to be 'back where we were' in Afghanistan as Taliban take over
• Defence Force to be deployed in Afghanistan to evacuate Kiwis, Afghan allies after Taliban takeover

"They won't be prepared for what you might be thinking of 'combat'," he said of the troops. "There'll be self-protection and self-protection rules, including individuals to protect the aircraft and make sure our asset can actually operate."

It could be the job of elite SAS forces.

"Not necessarily NZ SAS, it could be, we're still doing the planning," Ardern said. 

It's estimated 53 New Zealanders and 37 Afghan nationals will be flown out, along with their immediate families. 

"We're planning on hundreds of people," said Short. 

Raza Khadim is terrified for his family and for colleagues who worked with New Zealand in Afghanistan. He knows firsthand the threat posed by the Taliban, having worked as an interpreter for our Defence Force. 

"Barbaric," is how he described the Taliban. "They're not even humans the way they execute people."

He says locally employed Afghans played one of the most significant roles in running the Kiwi base in Bamiyan. It also made them instant Taliban targets. 

"You automatically become the enemy, a friend of the enemy is always the enemy."

And while some of those who worked with New Zealand hide on a mountain top - having been declined help until now - Canada announced last month it would resettle Afghans who worked with them, and the first group has already touched down. 

Investigative journalist and foreign correspondent Jon Stephenson told Newshub the Government could have acted sooner. 

"The writing has been on the wall for a long time and certainly the Government could have been more proactive, however the events have unfolded with astonishing rapidity."

Ardern says they moved as quickly as they could.  

"Given the circumstances and the information in front of us, we are doing everything that we can with the information we have at that time."

Twenty years ago, then-Prime Minister Helen Clark ordered our deployment to Afghanistan, and she believes the United States' rapid withdrawal has a lot to answer for and that some troops should have stayed.

"Two-and-a-half-thousand troops in Afghanistan for 20 years is not a huge commitment and probably was the difference between keeping precarious stability and being able to move forward, and the catastrophe we see today."

It's a catastrophe New Zealand spent 20 years trying to prevent.