According to an announcement made by Sunak on Sunday, 18-year-olds will be given a choice between a full-time placement in the armed forces or volunteering in their community.

The Conservative leader, who is hoping to boost his party’s popularity as it lags behind the opposition Labour Party by a wide margin in opinion polls, said the scheme would promote a “shared sense of purpose among our young people and a renewed sense of pride in our country”.

Opposition parties have criticised the scheme, saying its consequences for the economy and society are unclear.

How does national service work?

The proposed national service scheme is not the same as conscription, where people are legally bound to join the military for a period.

It instead gives young adults the option to choose between enrolling in a yearlong military training programme or carrying out civil service one weekend every month over the same period of time.

According to the proposal, the first option would require applying for one of up to 30,000 “selective” military placements reserved for teenagers deemed the “brightest and the best” in areas like logistics, cybersecurity, procurement and others.

Therefore, only a small minority of 18-year-olds would take part in any military training.

Home Secretary James Cleverly said no one would go to prison for not taking part but that there would be noncriminal sanctions for those who refused, without elaborating.

He did not specify if exemptions would be in place or if people in full-time education or employment would be able to defer.

It is not clear whether there would be a reimbursement for the yearlong military service, but the Conservative Party has said possible incentives could include “fast-tracked interviews” for graduate schemes in the private and public sector and “encouraging” employers to consider those who completed the military training.

The party said it would set up a public inquiry tasked with ironing out the details of the scheme should it win the election.

Its aim is to run a test programme by September 2025 and implement the whole scheme by the end of the next parliamentary mandate, which could be as late as 2029.

The scheme is estimated to cost 2.5 million pounds ($3.2bn). A portion of this sum would be raised by “cracking down on tax evasion and avoidance”, while the rest would come from the UK Shared Prosperity Fund set up to replace EU financial support to community organisations after the UK left the bloc.

Do other countries have similar schemes?

Mandatory military training for men aged 17-21 in the UK ended in 1960, though periods of deferred service were completed later on. In 2011, former Prime Minister David Cameron launched a voluntary scheme that saw young people take part in community projects, rather than military service, but it saw limited participation.

According to a 2023 YouGov poll, 64 percent of Britons oppose compulsory drafting, while voluntary schemes are supported by a majority of the population.

Many democracies still have some form of mandatory military service, while conscription is something that governments across Europe have been reluctant to reintroduce.

There are 66 countries that have mandatory military service, according to the World Population Review. However, many of them are not enforcing the rules to their full extent any more.

In the United States, for instance, the draft still exists but less than 1 percent of the population serves in the military. It relies on voluntary enlistment but also has a conscription system – known as the Selective Service – to fall back upon should the need arise.

The German government suspended compulsory military service in 2011, when its armed forces were transformed into a volunteer body.

France’s Emmanuel Macron, the first French president not to have done military service, campaigned to reintroduce mandatory military service that ended in 1997. In 2021, he introduced a voluntary period of one month in an effort to promote civic duty and national pride.

Fewer countries still enforce conscription. In Finland, the only NATO member bordering Russia, conscription remains mandatory for men and voluntary for women and varies in length from 165 to 347 days. Norway also holds a 12-19 month service obligation, while Sweden abolished compulsory military service in 2010 but reinstated a 6-15 month scheme in 2018.

Latvia most recently reintroduced conscription in January this year, having removed it in 2006. Estonia has maintained a form of conscription since its independence in 1991, but recently expanded the pool for callups.

Compulsory military service has long been a contentious matter in Taiwan, where it is widely unpopular among young people despite growing tensions with China. In January, the conscription period was extended from four months to one year as Beijing ramped up pressure on the island to assert its sovereignty claims.

Military service is also compulsory for all Brazilian men, but nationals living abroad can apply for discharge. Less than 10 percent of those inducted are estimated to be fulfilling the 10 to 12-months-long service obligation.

What is the controversy around the proposal?

Cleverly told the BBC that national service would engage young people in society again at a time when “too many live in their own bubble”. The policy, he said, would “address the fragmentation in society”.

“We want to get back to a situation where young people are mixing with people – in different areas, different economic groups, different religions – to try and find a way of addressing the kind of fragmentation that we see too much of,” the home secretary said.

Scottish Conservative leader Douglas Ross said mandatory national service would be a “great opportunity” for young people to get involved in the military, while voluntary work could tackle loneliness among older people in the public health system.

Opposition parties have criticised the proposal. Labour’s Shadow Chancellor Rachel Reeves told the British broadcaster that the plan was “a desperate gimmick from the Conservative Party with no viable means of funding it”.

Liberal Democrat leader Ed Davey said the Conservatives had “undermined the armed forces for too long” and that the military needed “professional soldiers, not people there for one year”.

The deputy leader of the Scottish National Party, Keith Brown, said he was firmly against the idea. “It’s a sticking plaster to cover up the disinvestment there’s been in the armed forces,” Brown, a former royal marine and Falklands War veteran, told BBC Scotland.

While he backed an increase in defence spending, he said the solution was to provide better salaries, housing and training to make the military career more attractive.

Scottish Labour leader Anas Sarwar argued the money should be spent on “stabilising our economy”, to deliver better healthcare and social services to the population.