But experts urge the government to avoid a vetting bottleneck by reducing private sector "churn" and removing artificial constraints to stop wait times being drawn out further.

The Coalition and Labor have both pledged to spend big on Australia's defence and national security ahead of the federal election in May, with the workforce set to get a significant boost.

Both parties are eager to show voters they're committed to keeping the country safe during turbulent times, in what analysts are calling the "khaki election".

Defence Minister Peter Dutton told voters last Thursday the government would invest further in the country's military if elected for a fourth term while voting Labor was a risk.

The boosted defence force, however, will result in more pressure being placed on the Australian Government Security Vetting Agency, as it works to process thousands more security clearance applications.

A spokesperson for the agency confirmed more than 70,000 clearances are likely to be processed this financial year - an increase of nearly 15 per cent on the previous year.

The spike in applications is being driven by the defence industry as well as non-defence agencies, the spokesperson said.

Vetting applications had also increased by 14.5 per cent during the financial year before with defence industry accounting for 30 per cent of that growth.

The vetting agency, long marred by backlogs since its inception in 2010, has struggled to entirely reduce wait times for its clearance process, failing to fully meet any of its time targets in its latest annual report.

While a target of a median 20 business days or less for processing baseline clearances was met, it was unable to process more than 80 per cent of baseline applications in that time period.

For priority cases of the highest security clearance level - Positive Vetting - less than half were processed in its target of 90 business days.

Former military intelligence director Professor John Blaxland said the backlog was harmful to the national interest and would compound if the government continued to outsource to the defence industry in this volatile era.

The industry's new prominence was largely in response to world events, such as the Russian invasion of Ukraine and China's posturing in the Pacific, he said.

Defence's 2020 strategic update had also prompted the industry's expansion in response to the threat of increased strategic competition and aggression, including "grey-zone tactics" designed to coerce states into conventional military responses.

A vetting agency spokesperson said it was able to easily increase and decrease its mostly contracted workforce depending on changes in demand to minimise possible wait times.

But Professor Blaxland said the issue, which was caused by two artificial constraints, could be easily fixed by the government.

Its policy of placing a cap on permanent Defence employees and personnel, and outsourcing their work to private industry, had falsely inflated the number of security clearances needed, he said.

Private-sector contractors brought on for short-term projects need to go through the vetting process each time one starts, and lose their clearance when it ends.

"The churn is significant and it's avoidable," Professor Blaxland said.

"The churn is artificially induced by the fact that the government refuses to allow these people to be hired as government employees.

"It's really just subcontracting government."

The vetting agency is in the process of introducing a new IT system, which it says will help streamline the process and automate some vetting activities. It is expected to come online in November this year.

Other government agencies outside of the defence and national security community are also expected to add to the security clearance load.

Professor Blaxland said public servants increasingly have access to more interconnected networks with sensitive information.

It means there are now more areas of vulnerability than ever before.

"With that connection comes risk of exposure and vulnerability to exploitation by potential adversaries, who are looking to inveigle their way into systems where they have no authority and no permission to," he said.

"That's a genuine factor."