China is developing a defense system to protect against laser weapons. It's unlikely to be a long-term solution, but for now the Chinese government is investigating the use of smokescreens in combat to defend against lasers.
Back in 2014, the US navy sent its first laser weapons into action: modest 30 kilowatt guns mounted on the USS Ponce. The weapons were aimed at providing defense against drones, slowly burning through their casing.
The Pentagon has plans to develop much more sophisticated laser weapons to disable anything from drones, mortar shells, rockets and missiles, according to Popular Science. As laser technology relies on the simple physics of light, smoke could seriously disrupt this type of weapon.
An article on China.com, which has links to the government, confirmed that research is being carried out into defensive smokescreens. This is likely to be a quick and low-cost solution, but over time laser weapons may be developed which can overcome the defense, requiring another approach.
The Chinese People's Liberation Army is exploring the creation of smoke in two ways: creating sulfur trioxide by burning materials, such as spraying oil on a hot diesel engine, or producing an oily fog. The PLA Chemical Corps plans to employ a new multiple canister launcher to lay the protective smoke screens.
Depending on weather conditions, smokescreens can last for a few minutes or many hours. They can also backfire on the forces they are intended to protect, for example by blowing back onto armed forces and leaving them unable to see.