US missile strikes against Syria send a clear message to North Korea but in the long run will only encourage the regime of Kim Jong Un to bolster its military and nuclear capabilities, analysts say.

The Tomahawk missile launches were an "indirect warning to Pyongyang that once North Korea crosses a red line, [US President Donald] Trump will not hesitate to to turn the US's power into action," said Youngshik Bong, a North Korea expert at Yonsei University in Seoul.

"This is far more effective in terms of etching a strong image of the Trump administration in the mind of Kim Jong Un . . . it shows Trump is not business as usual."

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Mr Bong said the attacks would create uncertainty in Pyongyang over how the US might attempt to put a halt to Pyongyang's increasingly sophisticated ballistic and nuclear weapons programmes.

Mr Trump told the Financial Times last week that the US could take unilateral action to eliminate the nuclear threat from North Korea — comments that raised the spectre of pre-emptive strikes — but he did not expand on his potential policies.

"Every statement that Trump makes about North Korea is important if for no other reason than that the North Koreans read it very carefully," said John Delury, another Yonsei University professor. "They're trying to piece together what the US policy is. Trump is almost intentionally cryptic about North Korea and that makes it harder for them to read what is he going to do.



On assuming office, Mr Trump ordered a review of US policy on North Korea and the results are expected soon. Officials have repeatedly said all options are on the table.

North Korea's foreign ministry issued an unusual memorandum on Thursday outlining how the country would respond to a conflict with the US and highlighting that it would focus its retaliatory measures on US bases, not civilian targets.

"[North Korea's] mode of attack, once launched, would be the precision strike to destroy only the military bases of the US and its vassal forces," the memo said.

"As already declared, the DPRK will also take all responsible measures for protecting the legal economic interests of other countries that they hold in South Korea."

For almost 70 years Pyongyang has invested heavily in its military in an effort to deter invasion. The country's nuclear weapon's programme is widely seen as a means for Mr Kim to ensure his survival.

"In the long run, [the Syria strikes] will only reinforce Kim's belief that 'we have to have nuclear weapons'," said Mr Bong. However, he added that Pyongyang would now be more more careful about how it proceeds.