Kirkenes, Norway (CNN)An American tank full of US Marines crashes through the silence of the sub-zero pine forest, far above the Arctic Circle, as unidentified drones hover overhead and yellow and green smoke fills the freezing air.
The troops' target? A bunker up ahead, manned by Norwegian soldiers. Shots ring out as the Marines advance, crunching through the snow beneath gray winter skies.
It's all role-play, of course -- the maneuvers are part of a training exercise, but one jarringly imbued with the new reality along NATO's northernmost border with Russia.
Some 300 US Marines are due to be based in Norway on a rotational basis from January, for a year, as part of a package of measures intended to reassure one of NATO's most easterly members.
Although they'll be about 1,000 kilometers (621 miles) from the border, the plan is for them to bolster the readiness of new "pre-positioned" tanks and weaponry stored throughout the year in underground caves.