Pyongyang has managed to increase the already elevated tensions on the Korean Peninsula in recent days with a number of military firsts. 

The latest actions by the North Korean regime underlined its burgeoning alliance with Russia, with the anticipated announcement of a summit between the reclusive nation's leader Kim Jong Un and Russian President Vladimir Putin in Vladivostok, on the Pacific Coast of Russia.

State media reported last week that Kim had overseen military exercises that simulated a "scorched earth" nuclear strike against the South followed by an invasion across the Demilitarized Zone that divides the peninsula and then the occupation of North Korea's ideological rival.  

The North said it had acted as South Korea and the US were plotting a pre-emptive nuclear assault on the North, adding, "The [Korean People's Army] staged a tactical nuclear strike simulating scorched-earth strikes at major command centers and operational airfields of the [South Korean] military gangsters."

The drills included the firing of two tactical ballistic missiles from mobile launchers close to Pyongyang.  

North Korea's 'clear message' to US, South Korea 

Pyongyang said it was sending a "clear message" to Seoul and Washington, which have recently completed the 11-day Ulchi Freedom Shield joint military exercise that included US nuclear-capable B-1B strategic bombers flying with a fighter escort over the peninsula.

The North insisted that the flights show the US was "moving toward a pre-planned nuclear pre-emptive strike against us."  

Pyongyang followed that exercise up with a "simulated tactical nuclear attack" on Saturday with the launch of two cruise missiles carrying dummy nuclear warheads, state-run media added.  

Analysts say that it is clear the North has made great strides in its development of nuclear weapons and long-range missile systems, but it has little chance of successfully invading and occupying the southern half of the peninsula — despite a standing army of 1.3 million service members.  

"In the past, the North Koreans invested heavily in artillery and building up their ammunition supplies, but virtually all of that is from the 1940s and 1950s," said Lance Gatling, a security and aerospace analyst and founder of Tokyo-based Gatling Associates. 

"So, while they have a tremendous amount of this stuff and rocket artillery, it is not very precise over long ranges. Also, the ubiquitous intelligence, surveillance and reconnaissance capabilities of advanced countries have a tremendous impact on any offensive capability they [North Korea] might have," he told DW.

Satellites orbiting at 500 kilometers (310 miles) above the Earth and with the ability to provide intelligence 24 hours a day and in all weather conditions means that any looming North Korean attack will be visible well in advance.  

North's ground forces outclassed 

Another problem the North faces is that it only has three potential ground routes of attack against the South, due to the geography of the peninsula, with any assault funneled into narrow areas and quickly resulting in what experts call "a cauldron of death" for the North's elderly tanks and under-equipped infantry units at the hands of the South and US forces. 

It would be a similar situation for the North's air force, said Garren Mulloy, a professor of international relations at Daito Bunka University in Japan and an expert on military issues.   

"Fighter pilots in NATO countries will put in a minimum of 200 hours of operational flying every year on the most advanced aircraft in their arsenals," he said. "It is estimated that North Korean pilots are only able to put in 20 hours a year due to shortages of fuel and their inability to obtain spare parts for their aircraft." 

There are additional question marks over the North's capabilities in other areas, including chemical, biological and bacteriological weapons, often dubbed the "poor man's nuclear weapons." 

"We know they have them and while no other country in the world would use them, we cannot entirely rule out the possibility of Pyongyang using these weapons, depending on just how threatened they felt," Mulloy said.

The North has no qualms about touting its nuclear capability, with the Seoul-based Korea Institute for Defense Analysis releasing a report in January estimating that Pyongyang's scientists have produced more than 2.2 tons of weapons-grade highly enriched uranium and as much as 78 kilograms (172 pounds) of plutonium.

That amount of fissile material would be sufficient for up to 90 warheads and, if development continues at the same pace, the institute believes North Korea could have 166 nuclear weapons by 2030. 

It is this saber that Pyongyang is now rattling, and with increased confidence as geopolitical events in other parts of the world have led to alliances of mutual convenience with both Russia and China.  

'Escalation of threats of violence'

"South Korea is not responsible for the escalation of these threats of violence from the North, although it has also been argued that the closer alliance between the South, the US and Japan has stimulated Pyongyang into those closer ties with Beijing and Moscow," said Lim Eun-jung, an associate professor of international studies at Kongju National University in South Korea.  

The upgraded Moscow-Pyongyang alliance is arguably the most significant change in recent years, with both sides benefiting.

Kim is expected to travel to Vladivostok by armored train later this month.

It is likely that the North Korean leader and Putin will use their meeting to agree the transfer of North Korean munitions in return for Russian fuel and foodstuffs.

Just as significant as a trade, which will benefit both sides, will be the optics of the developing alliance, which comes shortly after Russia proposed trilateral naval exercises also including China. 

But Pyongyang, already under a raft of international sanctions for its nuclear weapons program, has so far repeatedly denied supplying arms to Russia.

"The North originally got their shells from the Soviet Union and through China and have continued to manufacture this sort of ammunition, meaning they have huge stockpiles and they can keep making more," said Gatling. "They will sell their inventory and while it may be old it will still be effective and, for the North, valuable because these shells will allow them to bring in food and oil. 

"To me, it's clear that will strengthen both sides."  

Edited by: Srinivas Mazumdaru

Editor's Note: This article has been updated to include US reports that Kim Jong Un would travel to Russia to meet President Vladimir Putin in Vladivostok.