With its National Defense Strategy released earlier this year, the US detailed its shift from small-scale operations like counterinsurgency and toward a potential fight with a rival like Russia or China.
Countries around the world have made similar moves, refocusing on large-scale conflict.
Amid those changes, head-to-head comparisons of military strength are hard to come by. Global Firepower's 2018 Military Strength Ranking tries to fill that void by drawing on more than 55 factors to assign a Power Index score to 136 countries — adding Ireland, Montenegro, and Liberia to last year's list.
The ranking assesses the diversity of each country's weapons and pays particular attention to their available manpower. Geography, logistical capacity, available natural resources, and the status of local industry are also taken into account.
While recognized nuclear powers receive a bonus, their nuclear stockpiles are not factored into the score. Landlocked countries are not docked for lacking a navy, but countries with navies are penalized if there is a lack of diversity in their fleets.
NATO countries get a slight bonus because the alliance theoretically shares resources, but in general, a country's current political and military leadership was not considered (though financial health and stability is).
The top power index score is 0.0000, which is "realistically unattainabile" for any military according to Global Firepower. The closer they are to this number, the more powerful their miltary is.
Per these criteria, these are the 25 most powerful militaries in the world:
25. Canada
Power Index rating: 0.4356 (NATO member)
Total population: 35,623,680
Total military personnel: 88,000
Total aircraft strength: 413
Fighter aircraft: 60
Combat tanks: 80
Total naval assets: 63
Defense budget: $16.4 billion
24. Taiwan
Power Index rating: 0.4331
Total population: 23,508,428
Total military personnel: 1,932,500
Total aircraft strength: 843
Fighter aircraft: 286
Combat tanks: 2,005
Total naval assets: 87
Defense budget: $10.725 billion
23. Algeria
Power Index rating: 0.4296
Total population: 40,969,443
Total military personnel: 792,350
Total aircraft strength: 528
Fighter aircraft: 97
Combat tanks: 2,405
Total naval assets: 85
Defense budget: $10.57 billion
22. Poland
Power Index rating: 0.4276 (NATO member)
Total population: 38,476,269
Total military personnel: 184,650
Total aircraft strength: 466
Fighter aircraft: 99
Combat tanks: 1,065
Total naval assets: 83
Defense budget: $9.36 billion
21. Australia
Power Index rating: 0.4203
Total population: 23,232,413
Total military personnel: 79,700
Total aircraft strength: 469
Fighter aircraft: 78
Combat tanks: 59
Total naval assets: 47 (two aircraft carriers)
Defense budget: $26.3 billion
20. Vietnam
Power Index rating: 0.4098
Total population: 96,160,163
Total military personnel: 5,488,500
Total aircraft strength: 283
Fighter aircraft: 76
Combat 1,545
Total naval assets: 65
Defense budget: $3.365 billion
19. Spain
Power Index rating: 0.4079 (NATO member)
Total population: 48,958,159
Total military personnel: 174,700
Total aircraft strength: 524
Fighter aircraft: 122
Combat tanks: 327
Total naval assets: 46 (one aircraft carrier
Defense budget: $11.6 billion
18. North Korea
Power Index rating: 0.3876
Total population: 25,248,140
Total military personnel: 6,445,000
Total aircraft strength: 944
Fighter aircraft: 458
Combat tanks: 5,243
Total naval assets: 967
Defense budget: $7.5 billion
17. Pakistan
Power Index rating: 0.3689
Total population: 204,924,861
Total military personnel: 919,000
Total aircraft strength: 1,281
Fighter aircraft: 321
Combat tanks: 2,182
Total naval assets: 197
Defense budget: $7 billion
16. Israel
Power Index rating: 0.3444
Total population: 8,299,706
Total military personnel: 615,000
Total aircraft strength: 596
Fighter aircraft: 252
Combat tanks: 2,760
Total naval assets: 65
Defense budget: $20 billion
15. Indonesia
Power Index rating: 0.3266
Total population: 260,580,739
Total military personnel: 975,750
Total aircraft strength: 478
Fighter aircraft: 41
Combat tanks: 418
Total naval assets: 221
Defense budget: $6.9 billion
14. Brazil
Power Index rating: 0.3198
Total population: 207,353,391
Total military personnel: 1,987,000
Total aircraft strength: 723
Fighter aircraft: 43
Combat tanks: 469
Total naval assets: 110
Defense budget: $29.3 billion
13. Iran
Power Index rating: 0.3131
Total population: 82,021,564
Total military personnel: 934,000
Total aircraft strength: 505
Fighter aircraft: 150
Combat tanks: 1,650
Total naval assets: 398
Defense budget: $6.3 billion
12. Egypt
Power Index rating: 0.2751
Total population: 97,041,072
Total military personnel: 1,329,250
Total aircraft strength: 1,132
Fighter aircraft: 309
Combat tanks: 4,946
Total naval assets: 319 (two aircraft carriers)
Defense budget: $4.4 billion
11. Italy
Power Index rating: 0.2565 (NATO member)
Total population: 62,137,802
Total military personnel: 267,500
Total aircraft strength: 828
Fighter aircraft: 90
Combat tanks: 200
Total naval assets: 143 (two aircraft carriers)
Defense budget: $37.7 billion
10. Germany
Power Index rating: 0.2461 (NATO member)
Total population: 80,594,017
Total military personnel: 208,641
Total aircraft strength: 714
Fighter aircraft: 94
Combat tanks: 432
Total naval assets: 81
Defense budget: $45.2 billion
9. Turkey
Power Index rating: 0.2216 (NATO member)
Total population: 80,845,215
Total military personnel: 710,565
Total aircraft strength: 1,056
Fighter aircraft: 207
Combat tanks: 2,446
Total naval assets: 194
Defense budget: $10.2 billion
8. Japan
Power Index rating: 0.2107
Total population: 126,451,398
Total military personnel: 310,457
Total aircraft strength: 1,508
Fighter aircraft: 290
Combat tanks: 679
Total naval assets: 131 (four aircraft carriers)
Defense budget: $44 billion
7. South Korea
Power Index rating: 0.2001
Total population: 51,181,299
Total military personnel: 5,827,250
Total aircraft strength: 1,560
Fighter aircraft: 406
Combat tanks: 2,654
Total naval assets: 166 (one aircraft carrier)
Defense budget: $40 billion
6. United Kingdom
Power Index rating: 0.1917 (NATO member)
Total population: 64,769,452
Total military personnel: 279,230
Total aircraft strength: 832
Fighter aircraft: 103
Combat tanks 227
Total naval assets: 76 (two aircraft carriers)
Defense budget: $50 billion
5. France
Power Index rating: 0.1869 (NATO member)
Total population: 67,106,161
Total military personnel: 388,635
Total aircraft strength: 1,262
Fighter aircraft 299
Combat tanks: 406
Total naval assets: 118 (four aircraft carriers)
Defense budget: $40 billion
4. India
Power Index rating: 0.1417
Total population: 1,281,935,911
Total military personnel: 4,207,250
Total aircraft strength: 2,185
Fighter aircraft: 590
Combat tanks: 4,426
Total naval assets: 295 (one aircraft carrier)
Defense budget: $47 billion
3. China
Power Index rating: 0.0852
Total population: 1,379,302,771
Total military personnel: 2,693,000
Total aircraft strength: 3,035
Fighter aircraft: 1,125
Combat tanks: 7,716
Total naval assets: 714 (one aircraft carrier)
Defense budget: $151 billion
2. Russia
Power Index rating: 0.0841
Total population: 142,257,519
Total military personnel: 3,586,128
Total aircraft strength: 3,914
Fighter aircraft: 818
Combat tanks: 20,300
Total naval assets: 352 (one aircraft carrier out of service indefinitely)
Defense budget: $47 billion
1. United States
Power Index rating: 0.0818 (NATO member)
Total population: 326,625,791
Total military personnel: 2,083,100
Total aircraft: 13,362
Fighter aircraft: 1,962
Combat tanks: 5,884
Total naval assets: 415 (20 aircraft carriers)
Defense budget: $647 billion
Measure
Measure