India Just Tested A Submarine Capable Of Firing Nuclear Warheads From Sea

India's nuclear capabilities may have taken a major step forward.

On Monday, India began sea trials of its first nuclear ballistic missile submarine (SSBN), according to USNI news. 

The Arihant, a 112 meter 6,000 ton SSBN, left the Indian coast and traveled into the Bay of Bengal for tests after decades of development. The program to develop the submarine has been in place since the 1970s in an effort to create an indigenous submarine that could function as a nuclear deterrent. 

"Arihant is based on the Russian Navy's Akula-class design and can field 12 Sagarika submarine-launched ballistic missile (SLBM) with nuclear warheads,"  Sam LaGrone writes for USNI News. "The missiles are capable of a range of about 435 miles." 

India's launch of the Arihant coincides with a host of other military developments throughout South Asia. In October, India successfully tested a nuclear-capable cruise missile. Pakistan countered by carrying out a successful test of a nuclear-capable ballistic missile. 

The two nations are fierce rivals and have gone to war three times since British rule ended after World War II. A fragile ceasefire between the nations that has held since 2003 almost ended in October as both sides shelled the other over the disputed border in Kashmir. 

This mutual war footing between India and Pakistan, coupled with both nations' pursuits of nuclear weapons, has made a nuclear exchange on the subcontinent ever more likely, although still a vague possibility overall.

The eventual deployment of the Arihant may even help to stabilize relations between India and Pakistan through deterrence. SSBNs are capable of submerging at sea for months at a time, effectively allowing them to stay hidden and providing a "second-strike" capability that Pakistan currently lacks.

India's ability to launch a retaliatory strike against any Pakistani nuclear aggression would ideally convince both countries not to use their nuclear capabilities in the first place.