Now, the Pentagon will consider climate change when planning war games, US Defense Secretary Lloyd Austin said in a statement on Wednesday and declared it as a national security issue, reports The Hill. 

Austin said that there is little about what the defence department does to defend the US citizen that is not affected by climate change. "It is a national security issue, and we must treat it as such," the Defense Secretary said in a statement.

The defense department will take immediate appropriate policy actions to prioritise climate change consideration in the nation's activities and risk assessments, "to mitigate this driver of insecurity," Austin said in a statement. 

Austin's announcement came after US President Joe Biden earlier the day signed a series of executive orders in regard with the climate crisis, The Hill reports. 

The US Defense Department will now include security implications of the climate change in "risk analyses, strategy development, and planning guidance," Austin said. 

Austin said the Defense Department will also support "incorporating climate risk analysis into modeling, simulation, wargaming, analysis, and the next National Defense Strategy." 4

With this step, the US will change its approach on its carbon footprint, as the department will also be spurring the development of climate-friendly technologies at scale, Austin said. 

While the Pentagon since 2010 has recognised the climate change could pose a threat to the US's military operations and its roles and missions. However, it was never mentioned as a concern till now. 

In 2019, a report called the effects of a changing climate “a national security issue," the official version of the National Defense Strategy did not call for the concern. 

However, now, Biden's new push for climate change is creating a new shift in the White House, expanding the call from environmental agencies to those dealing with national security.

Climate change is now an "essential element of US foreign policy and national security," after Biden's new orders, the White House said.