President-elect Donald Trump should select Mitt Romney to be America’s next secretary of state.

On matters of both substance and style, Romney is a far preferable choice compared to the other two reported front-runners, Rudolph Giuliani and John Bolton. Giuliani’s undiplomatic demeanor, lack of diplomatic experience, and long list of potential conflicts of interest are just some of the reasons he should not be the nation’s top envoy. (Should Trump feel compelled to offer Giuliani a post, the Department of Homeland Security seems more suited to the former New York mayor and prosecutor.) Bolton has ample diplomatic experience, but his unbending bellicosity would make him ineffective.

Romney, conversely, has a diplomatic demeanor that contrasts not just with Giuliani and Bolton, but with Trump himself, whose impetuous comments run the risk of alienating allies and emboldening adversaries.

On policy, Romney was correct to point to Russia as a rising threat to global order during his 2012 run for the presidency. Four years later Russia’s destabilizing international actions prove it.

In Europe, Russia has illegally annexed Crimea, fomented a low-level war in eastern Ukraine that resulted in a downed passenger jet, continued its harassment of neighboring nations, and engaged in provocative military maneuvers in Europe that could spark a conflict. President Obama and the leaders of key European nations were right to agree to maintain sanctions on Russia after their meeting last week, and Romney’s prior positions suggest he would be a consistent advocate for continued Western unity in efforts to keep Moscow in check.

Elsewhere, Russia’s revanchist ways are seen in Syria, where Moscow’s immoral military backing of President Bashar Assad’s brutality against his own citizens has enabled a slaughter that should result in war crime charges. In just one stunning example of the human cost of Russia’s enabling, more than a quarter of a million residents of besieged Aleppo are left without a hospital after intense bombing over the last week, meaning that scores more will die in an already catastrophic conflict.

Solutions in Syria are not easy, just as other crises are hard to alter without directly engaging in the fighting. But Putin seems to be betting that he will not be held to account — and that the incoming administration is keen on improving relationships. As secretary of state, Romney, of course, would need to reflect Trump’s policies. But the formation of foreign policy in a Trump administration would benefit from having Romney’s counterbalance to the pro-Russian tilt Trump and other appointees seem to have.

Selecting Romney — the most notable figure of the never-Trump movement that took root among some in the GOP — would also be a magnanimous gesture for Trump. More important, it would signal to other substantive Republicans reluctant to serve in a Trump administration that duty to country can transcend politics.